Sponsored By Coors Light?

Colour-changing items based on temperature isn't something new. We've seen it used in mugs that change their images and colours when filled with hot beverages, we've seen Hypercolor clothing that changed colours with body heat, and we've seen the pictured Coors Light cans that show the mountains in blue when the can is cold enough. Even the British got in on the fun when they created stamps that changed from a gray sky to a blue sky in 2001! This technology has been around for a number of years, but it's 2018 which means that the NHL finally has jumped onboard with this decades-old colour-changing technology. The NHL announced today that the "official game pucks featuring thermochromic coatings supplied by PPG will be in play in the 2019 Bridgestone NHL Winter Classic" so that the officials know when a puck is no longer frozen and needs to be swapped out for a new, frozen one. Welcome to 1991, folks.

I use the 1991 year sarcastically because that was the year that Hypercolor clothing, containing thermochromes, was introduced to the world. Yes, I had a shirt back in grade school, but it quickly lost its appeal once the thermochromic effect was killed off by washing the shirt. On other words, you were either cool and had body odour or you had a non-working Hypercolor t-shirt and smelled fresh. I opted for the latter.

What makes this development by the NHL interesting is that the NHL was worried about the screening causing adhesion to the ice.

Thermochromic coatings supplied by PPG meet the NHL's requirements for withstanding game-environment impacts and low temperatures without impacting adhesion. The coating is dispersed into an ink system and screen printed directly onto an official NHL game puck.

Because adhesion to the ice surface should be the biggest worry when thinking about outdoor games and the possibility of melting ice due to the heat?

If the thermochromic puck gets too warm, the NHL logo on the back of the puck will go "clear", signalling to the officials that the puck needs to be changed. This is a greater concern than adhesion since we've seen a number of Winter Classic games with pucks that look more like bouncy rubber balls than hockey pucks. Dan Craig, the NHL Vice President of Facilities Operations, stated, "Freezing a puck eliminates bouncing, and game officials closely monitor the puck for temperature changes that affect performance while in play. A coating that changes color when the puck is above freezing will more accurately alert the officials that it is time for a replacement."

It's funny that the NHL just came up with this concept now considering there have been patents on this idea for years. Chromatic Technologies Incorporated is the company that allowed Coors Light cans to be thermally-regulated, and they've been working with the beer giant - one of the NHL's iconic sponsors for marquee events - for some time. It's almost as if the NHL is simply ignorant to solutions in other industries when it comes to solving their own problems.

In any case, it will be interesting to see how often the NHL changes out the puck based on how warm it is during the Winter Classic, how often the puck is handled by players and officials (hello, body heat!), how often it's lying on the ice (it should be colder), and how these pucks actually react if its warm when it comes to bouncing. If the screening on the bottom stays cold because it's being slid across cold ice, do the actual physical properties of rubber change (hint: no)?

What bothers me more is that if these pucks are single-use like Coors Light beer cans are, this seems like an awful lot of science going into something where an average of 12 pucks per game are being used. The NHL doesn't recover these pucks when they're shot into the crowd, so this seems like a ridiculous gimmick for something for which science should have already have an answer. And it does thanks to Alain Haché!

Look, I'm all for making the games better. Outdoor games are already a gimmick, and adding a colour-changing puck is just another gimmick within a gimmick. Like the FoxTrax puck, this idea, in its infancy, seems like a good idea, but the overall use in a long-term trial seems limited in its scope and depth. If these pucks are going to be used and sold as collector's items, I understand the merchandising effect of this, but using them indoors where 99.9% of all NHL games are played would be dumb at its very best.

If it's warm outside, the officials should be swapping out pucks as often as they can - that's just common sense. If it's sunny and cold, the officials should keep an eye on how the pucks are moving on the ice with respect to the black rubber absorbing the sun's heat. If it's cloudy and warm, the same respect should be given with the black rubber absorbing the heat from the environment. In the end, the officials are competent enough to do their job without a screen-printed thermometer on the puck that they have to check every time they pick the puck up.

The NHL loves its gimmicks. Get ready for another one.

Until next time, keep your sticks on the ice!