Viscospatula to the Rescue!
Custom decorators and product marking professionals have some common challenges, and one of them is print run consistency. Getting their ink to perform in the same way with the same quality from job to job, regardless of who is mixing the ink, has a better chance of success with some controls in place.
Ink series’ colors and batches can vary. Heat, cold and humidity can make inks thicker or thinner (their viscosity) from one run to the next. Viscosity affects the quality of the print job through ink absorption, color strength and evaporation/drying.
- Thick, high-viscosity inks are tacky and impede image transfer.
- Thin, low-viscosity inks run loosely to their own determined borders, changing halftone dot dimensions and blurring the image.
Although it is difficult to control variables such as atmospheric conditions, plastics decorators typically change machine settings or use additives to overcome these challenges when they occur. For experienced ink technicians, trial-and-error troubleshooting is second nature for correcting ink adhesion. For others, following ink manufacturer’s instructions and written notes — in conjunction with the PPMOVT Viscospatula — take the guesswork out of mixing ink and achieving consistently satisfactory results.
The Viscospatula is a simple, efficient tool used to achieve consistent and accurate ink viscosity when mixing pad printing inks. This tool has precision-milled holes and slots cut into a special ink-shedding fiberglass compound. When dipped into a prepared mixture, the ink flows down the spatula from the first hole to the fifth at a measurable rate, allowing adjustments to the ink’s thickness. The rule of thumb is: the thinner the ink, the faster it moves from the first hole to the last hole.
Using this tool to measure viscosity on a properly performing ink and noting the results with the job’s ink mix provides a roadmap toward future mixing success. Click Uneven ink thickness to see the Viscospatula and read more about it. We hope you never again have to explain why a reprint looks different from the original.
Join the conversation! Do you have a process to ensure reprint consistency? What tools do you use? Our technical ink experts are available to answer your questions and assist you in achieving ink nirvana. We answer any pad printing question!