When developing a process, it is important to know the exact time it takes for the coating to dry or cure. There are many stages to the coating drying time. Once a coating has been applied, the first stage is that the coating levels off under gravity. Once a coating begins to cure, a thin dry film appears on the surface .
But how to know when a coating is totally dry?
Using the Biuged Drying Time Recorder, the operator can easily identify each of the stages of the drying process:
A ball tip is placed into the coating and, using the mathematical formula: Distance=Speed ×Time ; the Recorder begins to move this ball at a predefined speed. As the coating dries, the trace left in the coating by the ball identifies each stage of the cure.
The various stages of drying and curing that occur in films are easy to detect but difficult to define in terms of chemical and physical principles. In order to evaluate them correctly, it is necessary to use instrumentation under controlled conditions.
Biuged offers a versatile drying time recorder to help quantify the various stages of film curing and drying, deliver reproducible results, and guarantee highest efficiency:
This reliable apparatus to test the drying time or gelation behavior of many paints and coatings, applied onto a glass strip of 330mm×24mm by means of our cube applicator (BGD 203). Hemispherical needles travel on these test tracks, over a selected time: 6,12 ,24 and 48 h.
The drying time stages can be easily assessed with the graduation scale (according to traverse speed configuration). The total time for every test can be observed from the LCD screen.
1. Evaporation of solvent: deep pear-shaped impression
2. Sol-gel transition: continuous track
3. Surface dry: interrupted track
4. Final dry time: the needle no longer penetrates the film