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Which cup material is the best insulator?

Which cup material is the best insulator?

If the three little pigs taught us anything, it’s that materials matter. Use the wrong material to make something and you may be in for an unpleasant surprise when you realize that material isn't up to the task.

Whether you’re trying to keep your coffee hot or your water cold, you need to make sure your cups are made from the highest-quality materials.

You need something that will protect your drinks from the outside elements and prevent the cup from sweating.

We find that 18/8 grade steel is the best insulator to protect both cold and hot drinks, which is why we use it in both our hot and cold products.

This material insulates cold drinks in the Cold1 Mug for up to 24 hours. It also insulates the Hot1 Mug, keeping contents piping hot for six hours.

After all, when you’re going to invest in a reusable mug, you should get one that works as hard as you do. 

Best: 18/8 Grade Steel

stainless steel best cup insulator
If 18/8 stainless steel is good enough to use in professional kitchens, it's good enough to make water bottles.

What is 18/8 grade steel? It’s all in the name – this type of steel is made of 18% chromium and 8% nickel, a powerhouse duo that reinforces the metal, making it extremely durable and resistant to both oxidation and corrosion. 

Highly Durable

When you invest in a reusable mug, you deserve a cup that will outlast hikes, picnics, multiple washes, and accidental drops - especially if you buy a kid’s mug

We use 18/8 grade stainless steel as the main material in both our Cold1 and Hot1 mugs because it’s so durable. In fact, this type of stainless steel is so strong that it’s commonly used to make kitchen equipment and storage tanks, not to mention truck bodies and wheel covers.

If engineers trust 18/8 grade steel to fortify and protect heavy-duty equipment, you can trust your 18/8 grade stainless steel water bottle to hold in your drink and keep it cold (or hot!)

Corrosion- and Oxidation-Resistant

The addition of nickel and chromium in the stainless steel makes our cups extremely resistant to corrosion and oxidation. Rust and discoloration are common examples of corrosion and oxidation. 

The last thing you want is a cup that will rust over time. That’s why we trust a stainless steel material that can withstand the elements without breaking down.  

Easy to Clean

Our stainless steel is also really easy to clean. The Performance Flask is made to hold 34 ounces of soup or hot liquid, but you can easily put it in the dishwasher too. Then all you have to do is give it a quick dry and put it away. It’s effortless! 

Worst: Aluminum

Turns out, aluminum is the worst cup material for insulation. It won’t keep your drinks hot or cold and it won’t last as long, either. Plus, if you continuously drink from aluminum cups or mugs, your body could build up toxic levels of aluminum. 

Good Conductor, Poor Insulator

Aluminum is a fantastic conductor of heat, which is why people use aluminum foil when they cook. This is great news for cooking, bad news for mugs and cups. Since it conducts heat so well, it doesn’t insulate drinks.

In other words, if you keep a hot drink in an aluminum cup, the heat from your drink will transfer to the cup and then to the outside air very quickly. 

Easily Deformed Under Air Pressure

Aluminum is also not very strong. It’s a better choice if you want a disposable cup that you can recycle immediately, much like an aluminum can. 

If you want something that you can use over again for many years, you’ll need something durable, like stainless steel. 

Exposure to High Levels is Toxic

Our bodies don’t get rid of aluminum when we accidentally consume tiny bits of it. Drinking from an aluminum cup, you run the risk of chipping bits of the cup off with your teeth. 

If your body accumulates too much aluminum, you could have a toxic reaction. 

It’s best to avoid this from happening by not drinking from aluminum cups. When you need to keep your mixed drink cold, use our Cold1 Chiller. It’s made with 18/8 stainless steel - safe for you and the environment. 

Science Is on Our Side 

Science can be fun - especially when it helps you keep your coffee hot and saves the environment at the same time! When you’re choosing a reusable mug, pick one of our cold products or choose from the hot collection

Reduce uses 18/8 grade stainless steel to create durable, insulated cups that’ll last for years to come, all without breaking down or exposing you to unsafe chemicals. Safe, durable, and effective - what more can you ask for?

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