FAQ: “How do I read Opacity on my MiniScan EZ (or ColorFlex EZ) instrument?”
To measure opacity you will first need to navigate to the product set up you wish to configure. Once in the product set up you will need to make sure that the standard is set to WORKING. Then navigate to the View you would like to configure. One in the view you will need to set your desired Display, Ill/Obs, and Color Scale. In the Color Index field use the left and right arrows to navigate to the OP (opacity) index.
FAQ: “Is there any way to lock the Product Setups on my MiniScan EZ (or ColorFlex EZ) instrument?”
Setups can be locked by navigating to Global Options from the main menu. In the Global Options menu you should see a Setups Locked field. Scroll down to the Setups Locked field and use the right arrow to select YES. Continue reading →
One thing to keep in mind when measuring creams, gels, pastes, and other semi-solid materials is to maintain a consistent sample thickness. One option is to “sandwich” a fixed quanity of your semi-solid material in a suitable clear-bottomed container, so that it can be placed at the port for measurement. Continue reading →
FAQ: “We are in touch with a pharmaceutical company which is looking for a spectrophotometer to measure the color and appearance of cationic surfactants. Can you provide any information on this topic?”
Surfactants reduce the surface tension of a liquid as in the use of a dish detergent; the interfacial tensions between two liquids such as in the case of an oil spill in water, or of laundry detergent removing soil from clothes in water.
Surfactants have two parts within a single molecular structure – a hydrophilic (or water-loving) head and a hydrophobic (water-repellent or oil-loving) tail. The hydrophobic part is typically a long hydrocarbon chain of different types. The polar hydrophilic head group can be non-ionic (no-charge),anionic (positive charge), cationic (negative charge) and zwitterionic (two opposite charges).
In terms of color and appearance quality, transparent surfactants are often visually described in product specification sheets as “clear and colorless”, almost “water white”, without apparent visual haze. “Colorless” in measurement terms, means being a close as possible to distilled water with only trace yellowness. Being “clear” means being as close to distilled water as possible in not scattering light.
How to Measure Surfactants on HunterLab Sphere Instruments
Any of HunterLab’s diffuse d/8° sphere instruments such as ColorQuest XE, UltraScan VIS or UltraScan PRO are appropriate for this application. Additional required accessories are a 50 mm path length transmittance cell (13-8573-20 or 20 mm path length cell ( 04-4592-00) and a Transmittance Cell Holder (C02-1005-481).
Configure the Color Data View in EasyMatch QC software to display:
CIE L*, a*, b* D65/10° or C/2° as a full color descriptor. While these values are good to report, APHA and Haze% will be the two metrics best able to distinguish slight lot differences in very clear and colorless surfactants.
APHA-50 mm [C/2°] or Yellowness Index YI E313 [C/2°] to quantify trace yellowness.Typical purchase specifications indicate a maximum APHA value of 5 to 30, with distilled water being 0.
Haze% to measure trace scattering to indicate how “clear” the sample is. DI water will have 0% haze. A visual difference in haze can typically be seen around 4%.
As an optional metric, Y Total Transmittance can be configured to quantify the total amount of light passing through the sample with DI water as a reference for 100% transmittance.
Standardize any HunterLab sphere instrument in TTRAN (Total Transmittance) LAV (Large Area of View) mode using:
The Light Blocker to set 0% transmittance.
The 50-mm path length transmittance cell filled with DI water and the white calibrated tile at the reflectance port to set 100% transmittance.
As a recommended PQ (Performance Qualification) step, leave the cell with DI water in place at the TTRAN port. Then measure DI water as a product standard. If the instrument is set up correctly, distilled water in the 50 mm cell should measure closely to CIE L* = 100.0, a* = 0.0, b* = 0.0; APHA = 0.0; YI E313 [C/2] = 0.0; Haze% = 0.0 and Y Total Transmittance = 100.0.
As an optional Application Diagnostic step, a liquid APHA Color standard can be purchased with nominal values similar to the product specification (APHA 5, 10, 20 or 30), then measured for APHA 50-mm and Haze% on the first day to establish baseline values. The measured baseline APHA value should closely match the assigned APHA value for the standard. The baseline Haze% should be low, typically < 1%. Measurements of the APHA liquid color standard should match the baseline values closely over time to affirm that your instrument is consistent in measuring APHA Color and Haze%.
Proceed to measure batch lots of surfactants and report APHA and Haze% to document process differences by lot and conformance to product color and appearance specifications.
FAQ: “We would like to access data outside the EasyMatch QC software. How can we export data from EasyMatch QC?”
In EasyMatch QC, we have an ASCII Export and Data Send features that can be set up to manually (batch export) or automatically (every new measurement) export to a file, COM port or IP address. The user can configure the data they want to send out of EasyMatch in ASCII characters with the delimiter symbol chosen for separation of the data pieces. They can then configure and parse their LIMs data collection system to bring the data format in.
Visual Evaluation of Color Samples in a Light Booth
FAQ: “I want to measure the lux level for a light box we are using to evaluate the color of garments. I would like to know, how many light boxes are required for a room. One light box has four D65 tube rods. My question, Is there any standard value of lux which we need to maintain and how do we find out for that lux level? How many light boxes will be enough.”
FAQ: “A customer would like to load EasyMatch QC software on a single server and then access EZMQC from several different terminals – is this possible?”
Unfortunately EZMQC does not support installation on a central server and activation from multiple computers, moving the hardware key from terminal to terminal to allow access.
As an alternative, EZMQC software could be installed on a single system (say a server) and then activated on a single terminal connected to the server via remote desktop sharing software or PC Sharing hardware. The hardware key would be installed in a USB port on the server.
FAQ: “We have a situation where a customer has 5 sensors and PCs along a line. Samples are being taken from the line and measured on the 5 different instruments at different points along the line, effectively monitoring the process. The customer wants to feed them into a common Job and Access Database.”
In EasyMatch QC, data can be saved in Jobs or a database (Access or Sequel Server). The key issue in allowing multiple PCs to save data into the same Jobs and/or database is whether the Jobs or database can “live update” with each measurement taken from multiple systems.
Live update can described as follows. Multiple HunterLab sensors are each connected to a personal computer and operate separately using EZMQC software on each PC. All systems are accessing the same Jobs and/or database such that when a measurement is taken from any of the multiple instruments, the central database or Job is updated. Live update allows this same reading to be recalled from the database and displayed automatically on all other EZMQC systems software.
EZMQC software does not have a live update feature that allows multiple users to access the same EZMQC Job or database simultaneously.
An alternative method to achieving the same result is to use the ASCII Export feature within each EasyMatch QC system to send data to a central LIMS (Laboratory Information Management System) for simultaneous viewing of measurement data.