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How to Seal Vinyl on Plastic Easily and Effectively

Most Cricut vinyl tutorials will end once the vinyl is applied, but later you’ll likely hear about one more common step in the vinyl decal application process: sealing vinyl.

Smooth plastics are undoubtedly one of the most optimal surfaces to work with when it comes to permanent vinyl decals, and you’re likely to achieve the best results possible. Keep in mind that plastics melt easily though, so we recommend staying away from iron on vinyl decals.

In order to seal permanent vinyl on your entire mug or another type of project, you’ll need to pick up the right brand of sealant and apply it to the mug. Apply the first thin layer and then the next, pausing between each coat to ensure that they stick. When that’s done, let the sealant rest for a while. We’ll let you know how long each of the sealant types needs before you can use your projects.

Sealing vinyl is a great way to give your project some extra durability—and we have all the information you need to start sealing!

Read on below if you want to learn how to seal vinyl decals on plastic.

how to seal vinyl on plastic easily and effectively

Do You Have to Seal Vinyl on Plastic Cups?

Adhesive vinyl stickers and plastic surfaces are a match made in heaven.

They work really well together, and you definitely won’t have any problems putting permanent adhesive vinyl onto plastic. Printable vinyl decals stick fairly easily, and when you seal them, they stick for good.

Depending on what you plan to use your project for and where you intend to use it, sealing the vinyl definitely isn’t 100% necessary. But just because you don’t need to seal vinyl doesn’t mean there aren’t benefits to doing it.

Sealing the craft projects you make can help improve them even further. Here’s why it’s best to seal your vinyl design.

More durable

Sealing vinyl means to add a ‘clear coat’ or ‘top coat’ over the top of the vinyl decal, be it on a mug or a stainless steel water bottle. It essentially adds a protective layer over the surface that stops the vinyl from being directly touched.

This means your vinyl stickers won’t peel off as easily, get caught on things, or be damaged by sharp objects. They’ll also survive repeated washings.

One instant advantage of this is that you won’t need to handle your project like a project anymore—no need to be hyper-aware of the delicate sections or put too much thought into how you hold your mugs or water bottles.

All sealants are different (and we’ll cover this in detail later), but the minimum they all do is give the surface of your craft projects protection from light, water, and extreme temperatures.

Some sealants will be heavy duty enough to do this even in outdoor conditions, and others will just protect from lesser influences found indoors. We will help you choose the right sealant for all kinds of vinyl, be it regular vinyl, permanent vinyl, or mirror adhesive vinyl.

Lasts longer

Part of your vinyl project being more durable is that it will last longer. Even though you’re not handling it with extra care anymore, it will still keep to its original condition for longer than it would prior to you making the choice to seal vinyl.

This is a particularly useful advantage when giving your projects as gifts. Vinyl decals are often found on plastic mugs or plastic water bottles, both of which make thoughtful and personalized presents.

Looks better

This is dependent on your sense of aesthetics, but many people think their vinyl looks a lot better and more professional once it is sealed. This is because the clear coat creates a smooth surface and helps minimize the ‘stuck on’ look of your vinyl decal.

In other words, it stops the edges of the vinyl from standing out and looking like you’ve simply slapped a normal sticker onto your project. 

Easy to clean

No matter what kind of sealant you use, your vinyl will be given some protection from water and you will create a nice smooth top surface that is easy to clean. But, if you make the right choices with your sealant, you can even produce vinyl mugs, water bottles, and dishes that can survive the dishwasher.

This is a huge deal for crafts given as gifts because they would probably get put in the dishwasher either way and this way you can stop the surface of those mugs from degrading. We call sealants with this feature ‘dishwasher-safe’, and there are multiple options to choose from.

Read on if you’re interested in finding out the best vinyl sealant for you!

What Can You Use to Seal Vinyl Decals on Plastic?

Below, we will walk you through four different types of sealant and what each of them can do.

They vary in price, accessibility, ease of use, and quality of result, so think about what your particular plastic project needs, and what you want from your sealant. 

1. Mod Podge

This brand of decoupage sealant is so popular that you’ll sometimes hear this name used to refer to any and all kinds of sealant or varnish. You’ll also likely hear it pronounced ‘modge podge’, perhaps because it sounds more approachable.

Mod Podge is definitely the most accessible and cheap option on this list, and you’ll find it on Amazon as well as in your local craft stores.

It’s aimed at the average home crafter, is easy to use, and it’s non-toxic so it can be used with older kids. It is not, however, approved by the FDA. This means that you should not apply to a surface that will make contact with your mouth.

This is especially important if you’re applying Mod Podge to dishes, such as a glitter mug or a water bottle. In those cases, make sure you don’t cover the entire mug or water bottle as you seal vinyl with Mod Podge.

Mod Podge also comes in a number of varieties including matte finish, glossy finish, glitter finish, and one you can put in a dishwasher. Mod Podge is not a very thick sealant, so the glitter types will produce a textured finish, and reviews of the dishwasher safe Mod Podge are mixed. Therefore, hand washing the mugs is always the safer option.

This sealant comes in a tub and is generally applied with a paint brush. However, you can also use a foam brush or sponge brush in order to minimize streaks and brush marks. 

Cure time

This refers to the amount of time you need to wait before using your Cricut vinyl craft (if it’s a usable object like a mug or dish). While the sealant will dry in a couple of hours, Mod Podge requires you to then keep your craft in a dark dry spot for 28 days before using it! 

This is often seen as the biggest downfall of modge podge, because it becomes completely out of the question for crafts that you wish to give away in less than a month. 

If you need to seal vinyl quickly, check out our other recommendations.

2. Triple Thick

This is the other popular vinyl sealant option you are most likely to find in your local craft store or online. The main difference between Triple Thick and Mod Podge are texture and thickness.

This sealing agent prides itself on having a very thick consistency, so you should definitely only buy it if thick is what you’re aiming for. 

As for why you might want a particularly thick layer— there are two main reasons. The first is that it can give you a smooth finish even with a textured vinyl, like something you’d stick on to create a glitter mug.

There’s nothing wrong with a bit of texture, but sometimes it won’t be the final look you want for your plastic craft and at times like that, Triple Thick is your best friend.

Secondly, although Triple Thick does not sell itself as a dishwasher-safe sealant, it’s so thick and tough that it can do quite a good job anyway.

You shouldn’t expect a 100% dishwasher-safe product, but there are definitely people out there that prefer to use Triple Thick compared to the dishwasher safe Mod Podge.

Bear in mind that it is always best to put vinyl mugs in the top rack of your dishwasher. 

Cure time

Triple Thick will dry in a few hours and can be lightly used after 48 hours. Seven days is the recommended time for a full cure. 

3. Polycrylic 

Polycrylic is a water based multitasking sealant and varnish that is often used with woods, but it works wonders with plastic too.

The selling point of this sealant is that it can come in spray form like spray paint and is really quick and easy to apply. 

The downside of this, though, is that it can only be applied in a really thin layer, so you’ll need to wait for each coat to dry before adding another.

The amount of coats you add is completely up to you though, so it doesn’t have to take up too much time. 

Polycrylic is not a heavy duty sealant, is not made for outdoor use, and it isn’t dishwasher-safe. You should always hand wash plastic cups and mugs regularly when they are sealed with spray sealer.

This is an all-in-one sealant that you can use for just a little extra protection when you don’t have any specific needs that need to be addressed.

For example, a sweet little plastic ornament that is destined to just sit happily on your mantelpiece: this kind of project works perfectly with polycrylic. 

There is another type of spray sealant you might see in the same aisle as polycrylic, and this is called polyurethane.

It’s oil-based and far more heavy duty than polycrylic, and thus, it’s meant for outdoor use. It also tends to dry with a yellow tint, so we recommend that you don’t accidentally buy this for your indoor Cricut vinyl crafts! 

Cure time

For a few thin coats of polycrylic, the average craft will take between 24-72 hours to cure. A craft can be subjected to light use after around 24 hours. 

However, depending on the thickness of the coats and the number of coats applied, polycrylic could take up to three weeks to fully cure.

4. Epoxy resin

This final sealant is the king of all sealants. It is not a beginner-friendly crafting technique, and due to expense and difficulty, we can’t really recommend using it for no good reason.

However, if you need the best possible results, epoxy resin is a generally safe bet.

You may have heard of epoxy resin before because it is used in all sorts of crafts.

It will give your mug (and other vinyl crafts) a beautiful glossy finish and it’s great at smoothing itself out to create neat layers. 

Epoxy resin is also the only sealant on this list that is truly 100% dishwasher-safe, and it is also FDA approved and food-safe. 

So, what are the downsides? Firstly, it is more expensive to buy than any of the other sealants.

Secondly, you’ll likely end up wasting some. The way epoxy resin works is that you need to mix two liquids together to make it. 

As soon as these liquids touch, they’ll begin a chemical reaction that will slowly harden the mixture.

You will have plenty of time to stick the resin to your craft, but it will be impossible to reuse any leftover resin because it will eventually harden. 

Additionally, some epoxy resins will require you to continuously stir the two liquids for over ten minutes!

Cure time

Epoxy resin will usually take around 72 hours for a full cure.

You should make sure not to touch or move the project until the time is up as you could risk damaging the beautiful glossy finish. 

How to Seal Vinyl Decals on Plastic Step-by-Step

Now that you know what you can use to seal vinyl onto plastic crafts, make sure to follow our guide to putting vinyl behind a secure layer of sealant.

Step 1 – Wait time

There are some sources that claim sealant could negatively affect the adhesive on your vinyl sticker.

In order to minimize the chances of this happening, we recommend leaving your vinyl to dry and cure for around 24 hours before applying sealant. 

Step 2 – Work quickly 

When applying sealants with a paint brush or foam brush, it’s best to work quickly.

Sealant can begin to harden pretty quickly, continuing to disturb it with a brush will result in streak marks that won’t go away as effectively. 

Step 3 – Only use as many layers as you need

It might seem tempting to just keep adding coats of sealant indefinitely because the more you have the better protected your craft will be, right?

But that’s not really the case. Having too many layers or coats that are too thick will result in suboptimal results and will extend the cure time by quite a lot. 

Think about what your craft will be used for, where it will be used, and how much wear and tear you expect it to encounter.

Sometimes, just two coats of spray sealant will be all you need, and other times you’ll want to splash out on epoxy resin. 

Step 4 – Don’t ignore the cure time

It might seem very annoying to have to leave your craft alone for 24 hours, 72 hours, 7 days, or even a whole month—but it does need to be done after you seal vinyl.

If you try to use your craft before the recommended cure time is up, you’ll only end up wasting all of your hard work. From your first steps with a Cricut cutting machine to the moment you seal vinyl, it’s a long road, so make sure you give your decals enough time to cure before you move on with each step.

Sealing Vinyl on Plastic: FAQs

We’re nearing the end of our guide—you’re pretty much an expert on sealing vinyl by now! However, to leave you with some extra important knowledge, we’ll give you more tips in our quick FAQ section below.

1. Can you use Mod Podge to seal vinyl on plastic?

Absolutely! Mod Podge is a very popular vinyl sealant that does the job wonderfully on all kinds of plastic. It comes in various options, from glossy to matte, and is non-toxic, so you can easily use modge podge during a craft night with the kids.

Keep in mind, however, that Mod Podge is not approved by the FDA. This means that you cannot apply it to the parts of your mug that your lips may ever touch. As long as your decal doesn’t require a full seal, you can use Mod Podge without a single worry.

2. Can I use iron on vinyl on plastic?

Unfortunately, using iron vinyl decals on plastic is a really bad idea. This type of vinyl is referred to as heat transfer vinyl and it requires heating up the decal prior to applying it to your mugs. You know what this means, right? Ultra hot substances and plastic unfortunately do not mix. As such, make sure you never use this type of vinyl on your plastic mug.


Sealing vinyl onto your plastic crafts is a great way to protect them and ready them for the wear and tear of the world.

Depending on what your craft will be used for, you can apply specialist sealants that are dishwasher-safe, non-toxic, or FDA approved to really give your seal craft projects a professional look and quality.

If you’re worried about getting the best quality of vinyl decals, don’t forget that you can use a cutting machine to neatly cut out the material before putting vinyl on your project. Such machines can easily be found online.

Once you’re happy with how your vinyl craft looks, seal it to make it serve you for the years to come.

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