When to Use a Wet Application Technique for Window Graphics
Written by: Molly Waters, Technical Specialist, Avery Dennison, Graphic Solutions, Avery Dennison on news.averydennison.com/blog
Many vinyl film manufacturers recommend using a dry application process. I agree with this general rule, for the most part, because, once you learn the proper application techniques, a dry graphics application can be faster and much cleaner than a wet application.
However, there are certain situations when wet is the way to go. In this blog post, I am going to specifically address wet applications for windows.
Why wet? If you are installing an etched glass film, frosted film or a graphic printed on clear film on a window, it is likely this film does not include the air egress channels that prevent air bubbles from forming during installation.
In these cases, installers will use the wet application method to achieve an ideal solution. Not only does the wet installation method help eliminate air bubbles from forming, it also eliminates the squeegee marks in the adhesive that you normally see right after an installation. Those squeegee lines generally go away once the adhesive wets out, but the wet application lets you avoid this altogether.
Under no circumstances is it OK to wet-apply perforated window film or air egress products. Water will be trapped behind the graphic and cause it to fail.
When applying a graphic using the wet application method, there are several steps you should take to ensure the application goes well.
Test the film. First and foremost, make sure the adhesive is going to be compatible with wet application.
Have you ever applied a clear film using wet application and had it turn white? If so, this is because the adhesive was most likely an emulsion adhesive, which is not suitable for wet application. I’ve had many customers report that once they had the adhesive turn white it never “dried out” and went clear again.
It is easy to check the adhesive type. Simply place a strip of the film you are about to apply in a cup of water, let it sit for 30-60 seconds, and then pull it out. If the adhesive is still clear, then you will most likely be OK going forward with a wet application. If it turns white, wet application is not an option.
Be patient. If you are applying a graphic with pre-mask or application tape, be aware that you may need to allow the graphic adhesion to build for a period of time before removing the mask or tape.
If you remove them too soon, you will see that the decal wants to lift back off of the window. Sometimes spraying the paper pre-mask with your application fluid can help the glue release from the decal. Note: this trick won’t work on a non-paper pre-mask.
Follow instructions. The third thing to watch is application fluid. Many people like to use soap and water for their application fluid, and this is OK. However, you need to make sure the soap being used does not contain any perfumes or lotions. These can act as a contaminant and weaken the graphic adhesion.
Also, more is NOT always better. If the instructions say to use 1 teaspoon of soap per gallon, it is not safe to assume that 2 teaspoons is better. This may help the graphic slide around on the window better, but it will also prevent the graphic from sticking as well.
If you are using an application fluid from concentrate, please be sure to follow the manufacturers’ recommendations for mixing.
I usually use a 25% isopropyl alcohol to 75% water mix. I like this solution because it seems to dry faster so the application tape can be removed sooner. The disadvantage to a shorter drying time is that you may need to reapply the solution during the application. To me, though, this is a fair trade off.
Wet Installation Process
In order to prep the window for the graphic application, you should clean the window as you would for any application.
When it’s time to apply the graphic, you will spray the window as well as the exposed adhesive with the application solution. Depending on the graphic size, you may need a second set of hands to remove the liner and hold the graphic while spraying it.
Next, position the graphic on the window. The nice thing about wet installation is that you can slide the panel into place.
Then use your squeegee to push the water out from under the graphic. Most people like to start in the center and work their way towards the edge. Use firm, overlapping strokes. If you do not have application tape on the graphic you may want to spray a little of the fluid on the front of the graphic to “lubricate” the squeegee and minimize any scratching.
Once you are finished squeegeeing the water out, the next thing to do is use a dry, lint-free towel to wipe up all of the excess application fluid and clean up your work area.
Then you can stand back and admire your work.
For more information about Avery Dennison Graphics Solutions, visit www.graphics.averydennison.com.