Avoid viscosity problems with regular checks, using an S90 Zahn Signature Dip Viscosity Cup (a pH Meter used in combination with the Zahn Cup will go a long way towards improving print quality).
Read our newest viscosity article on FlexoExchange:
Measuring Viscosity with a Zahn cup? Use Centistokes, not just Seconds!
S90/Zahn Signature dip Viscosity cups are an improved version of the time honored Zahn Signature viscosity cups. GARDCO is the only producer authorized to use the Zahn name and has added the S90 designation to identify the improved viscosity cups manufactured on new state-of-the-art equipment to ensure optimum quality and uniformity. Calibration of the S90/Zahn cups match the earlier Zahn Signature cups. Conversion formulas and tables relating cup efflux time in seconds to viscosity in centistokes are identical for both series of Signature cups. S90/Zahn cups are calibrated with standard "G" series oils traceable to the National Institute of Standards & Technology. "G" series calibration oils are produced in accordance with ISO 9002.
For those users who require documented certification of their measuring equipment, you may order a CERTIFICATE of CALIBRATION ($140.00 additional charge) . This document contains not only information on actual cup calibration with standard oils traceable to the National Institute of Standards and Technology but in addition, this certification also complies to conditions and procedures under the requirements of ANSI/NCSL Z54O-1 or MIL-STD-45662A as applicable.
* #1 - #5 Zahn Cups Available (most flexo inks are measured with a #2 or a #3)
* Monitor Ink Viscosity
* Maintain Print Quality
| Cup Number |
Seconds Efflux Time |
Centistokes Range |
Oil Used to Calibrate |
| 1 |
31-60 |
15-78 |
G-20 |
| 2 |
19-60 |
39-238 |
G-60 |
| 3 |
11-60 |
63-604 |
G-100 |
| 4 |
10-60 |
97-899 |
G-350 |
| 5 |
10-60 |
219-1627 |
G-350 |