One of the top questions we hear at GoSili is, “What makes your cups so strong at the lip?” The answer? A brilliant—and slightly unexpected—discovery from over a decade ago. This is the story of how a stainless steel ring became the secret sauce in our silicone cups.
The Challenge with Pure Silicone
When GoSili first set out to replace single-use plastic cups, silicone seemed like the perfect solution—non-toxic, reusable, and built to last. But there was one problem: silicone is naturally soft and squishy. Great for flexibility, not so great for creating a cup with a sturdy lip.
Our Creative Director, Giuliana Schwab, got to work in 2010, determined to design a silicone cup that could hold its shape, stand up to daily use, and replace disposable plastics for good. The challenge? No flimsy, collapsible cups allowed!
Enter Stainless Steel (Hello, Game-Changer)
After some trial and error, stainless steel emerged as the hero we didn’t know we needed. By adding a stainless steel ring inside the cup’s lip, we could give it the structure and stability it needed—without sacrificing our commitment to keeping things non-toxic and plastic-free. The first prototypes were a hit, and the stainless steel ring became a GoSili signature feature.
But before we popped the champagne, we needed to answer one burning question: could the cups survive the microwave test?
“Wait… Can I Microwave This Thing?”
Giuliana, having grown up without a microwave, didn’t fully grasp the golden rule: metal + microwaves = bad news. So, when she confidently popped the cup into the microwave, her husband stopped her mid-button-press with, “What are you doing?”
Curious, she tested the cup anyway. What followed was an unexpected back-and-forth that led to a surprising discovery. After testing the cup in the microwave for 10 seconds, 30 seconds, 1 minute, and even 5 minutes, the results were puzzling. While the liquid inside heated up, the stainless steel rim of the cup remained completely cool to the touch. And no fire or explosion. Wait, what?
Shocked, the team dug deeper and uncovered an interesting fact: smooth, rounded metal surfaces—like the stainless steel band on their cup—can actually be microwave-safe. Unlike jagged or sharp-edged metals, these surfaces don’t cause erratic electron collisions, meaning they won’t spark or create hazards in the microwave. Who knew science could be so fun?
Professional Stamp of Approval
To be sure, we sent the cups to a third-party testing facility. Fun fact: even the lab was hesitant to microwave metal. So, we bought them a microwave, shipped it along with the cups, and let them run the tests. Spoiler alert: the cups passed with flying colors. (We never got that microwave back, by the way.)
14 Years Later… Still Going Strong
Today, GoSili cups with their patented stainless steel rings are a favorite among eco-conscious consumers. They’re durable, safe, sustainable, and—let’s be honest—just plain cool.
The stainless steel ring isn’t just a clever design tweak; it’s a testament to innovation and sustainability coming together. At GoSili, we’re proof that small changes can make a big impact—for people, the planet, and your favorite drink.
Sustainability is the future, and we’re here for it. Cheers to that!
