is reader-supported. When you buy via the links on our site, we may earn an affiliate commission at no cost to you.

How to Seal Sharpie on Plastic?


Have you ever tried writing on plastic with a sharpie or a permanent marker? Have you been working on an art project that needs a permanent marker writing on a plastic surface? If so, you might be thinking about the best ways on how to seal sharpie on plastic and make it adhere to the surface for a long time. In the following, we’re discussing simple methods to prevent the ink from smearing as well as rubbing off that they disappear completely from the plastic surface.

Preparing the Surface With a Sandpaper

Typically, plastics have a nonabsorbent and smooth surface, which wanes down its adhesion, but this can be restored using a sandpaper. You can use it to make a porous, rough texture, which can eventually make a more adhesive surface. It will let the permanent marker stick to the surface and avoid any smearing in the end.

You need to know what sandpaper to use in performing this task because it’s what you’re going to use in polishing the plastic surface and removing the imperfections later. For this task, you need sandpaper with grit between 80 to 120 grit sandpaper.

However, check that you have cleaned the surface and removed any oils and dirt before sanding. You must also use a damp cloth, which will clean the target area on the plastic surface. When done, you must use a wipe again using a dry cloth. After, do the final cleaning, soak your cotton ball in rubbing alcohol to prepare the surface. Allow it to dry.

Now, you’re ready to polish the surface on where to write with your sandpaper. You don’t need to sand the entire area or material, though. Once finished sanding, you can see remnants or small particles. Simply clean or remove them using a soft and dry cloth.

After preparing the work surface, start writing. You’ll notice that it is easier to work on now that it already has a rough texture on it. But then, take note that what you write on it won’t be erasable anymore.After writing, you can just let the ink dry overnight.

Buying Permanent Markers

For the best results, you must buy the right kind of markers. Not all of them would work on plastic; thus, investigate a little and determine which kind would work well on plastic surfaces. When buying, check that the markers are compatible with plastic. The same is true for choosing a marker for a specific type of surface.

Stay away from oil-based markers because they don’t work well on plastic surfaces aside from not drying. They can also lead to ink pooling and smudging.

Test the marker before writing to see if the ink skips. It will also help you prevent any bleeding, spills, and smudging.

To improve the adhesive properties of the surface, sand it first. You don’t have to sand the entire item but only the target area. You must also remove any small particles of dust using a clean and dry cloth.

When done testing, start writing, and then allow the ink to dry overnight to dry the ink. Don’t forget to replace the cap so that it won’t dry out.

Methods on How to Seal Sharpie on Plastic

1. Using a mod podge mattifying sealer

This is a multipurpose and useful sealer that can work well for the job. In fact, you’ll be surprised at how effective it is when it comes to sealing. It can work like a fixative, so it can completely protect the art from smudge and make it water-resistant.

Prepare the plastic surface before applying this product. To do it, use a damp cloth to remove any dirt.

Use a 120-grit sandpaper to prepare the plastic surface so that you can make it rough and allow the ink to securely stick to it. When done, you must wipe the residues using a cloth.

Allow the surface to dry overnight quickly before writing on it. To write a design, use your marker, and then let it dry overnight.

When done, you can apply the glue over the design so that you can seal it. Again, allow it to dry. Once dry, you can notice that there is a matte finish on the surface, and it will keep the sharpie sealed on the plastic.

Alternatively, you can use Mod Podge acrylic spray sealer. However, ensure that you’re keeping it away from the surface for up to eight inches. Once done, you can spray some of it and then allow the spray to dry for up to 48 hours for the best results.

2. Using nail polish

Nail polish is effective because it is made with stabilizers, thickeners, and polymers, which are coating your nails and leaving them with a shimmery finish.

It is not just for beautifying your nails but also sealing sharpie on plastic surfaces. Yes, that’s right. You can also use it in this task without any hassle. Nail polish is also easy to find in your home as well as in the store, so you won’t have a hard time to use it in sealing permanent markers on plastic at all.

Prepare the surface to clean any dust and oil as well as making the surface more adhesive. Sand the plastic surface so that you can form a little bit of a rough texture on it. When done, you can start writing on the plastic.And again, allow the writing to dry before applying a nail polish layer. Just make a single layer in a single direction. Do not apply multiple coatings because this can lead to long drying time and uneven coating.But if you need to add another layer, just make sure to dry it in order that it can leave a protective layer.

Final thoughts

There are several ways to ensure that permanent markers remain on plastic. Again, you can use the protective sealers mentioned earlier. However, always prepare the surface with sandpaper and clean cloth. Plus, you must choose the right pens for the job, including sharpie pens. And in the end, make sure that you dry the ink overnight.

Did you like the article on how to seal sharpie on plastic? Tell us in the comments. Finally, share this post on social media and help your friends learn the same information today!

Leave a Comment