A New Use for an Old Technology; Thermoball Insulation

Sometime back when DuPont Corporation still manufactured polyester fiber they developed small balls of polyester similar to cotton balls and placed it in pillow ticking for pillows. They called this fiberfill product “cluster fiber”. Since it was never introduced to the outerwear market as an insulating medium I was not aware of its existence. I just read an article in Popular Science about these cluster fiberfill balls being used as an insulating medium by The North Face Company (TNF); they call this insulation “Thermoballs”.

TNF is groping at straws with this product. In order to use it, it has to be inserted in baffles just like down. Why are they going in this direction, I believe they believe from what I have read this product is as close to down as it gets and therefore, it is better than other fiberfill’s. Unfortunately for TNF they do not have any employees with any real knowledge of synthetic insulations so this is nothing more than a marketing ploy.

It all came about when the mountaineer they promote Conrad Anker (CA) and the rest of TNF climbing team in 2008 had to abort an attempt to climb Mount Meru in India’s Garhwal Himalaya. It is not stated in the article the specific reason that the climb was aborted, but it is obvious that they were probably freezing as their down insulated clothing was absorbing the moisture they were generating. They were probably having the same experience with their sleeping bags. As is stated in the article CA “request for a better synthetic”. Strange because since the 1930’s when Eddie Bauer Company started making down insulated outerwear, down has been the choice of climbers all over the world. Is this the first time a climbing party has had this problem; NO. Climbers in my opinion will brutalize themselves saving weight. Down has historically had a reputation that it no longer deserves that it is the lightest weight most efficient form of insulation. Continuous filament fiberfill when used to its best advantage is so superior to all other forms of insulation, to include Thermoballs, it even makes down obsolete.

According to the article; “Thermoball, created by noted outdoors/college campuses company North Face, is a synthetic insulation that closely mimics down. Unlike traditional continuous-filament synthetic insulations, which are laid out in flat sheets comprised of thousands of long filaments. Thermoball is made from short strands of polyester that have been spun and frayed into millions of fuzzy miniature cotton-ball-like balls, 0.15-0.2 inches in diameter (about the size of an oval M&M). They float inside hundreds of tiny pockets, or baffles, sewn into a jacket. They are designed to cluster like feathers, maintaining air pockets (which are key for retaining warmth) rather than clumping together into a solid mass”. Imagine that they take credit for creating a product that already existed; and I didn’t know they were an “outdoors/college campus company”. Exactly what does that mean?

Many years ago (during the 1960’s) there existed a company Holubar located in Boulder Colorado. They made a down parka and pant that was of a baffle construction. They sold very few because the cost was significantly greater than the standard quilt through construction. Of course TNF is making these in China so the cost is $0.50 per hour, maybe. The published retail price is $280.00. A retailer selling this parka is paying approximately $155.00. TNF might be paying as much as $125.00. The manufacturer may not be making any profit because the labor to make this jacket must take 8 hours.That aside as this garment is used the balls of polyester are going to degenerate, collapse which will reduce the heat retention capability, which is not much to begin with. I would be surprised if the garment were good for a temperature nearing 0 degrees F. That is the nature of chopped staple fiber; they chose to call it “short strands of polyester”. It will not clump in a solid mass as down does when it gets wet. However, it will get soaked as CA states and I quote; “I noticed it stayed warm even when it got soaked with sweat on a long run”. He should have included in his comment the temperature during his time running which I suspect was above 32 degrees. If it were colder I doubt he would be warm. The fact that it trapped the moisture is simply not a good sign. The moisture trapped in the fiber will ultimately absorb heat being produced by the wearer of the garment causing a chill. If he were wearing a garment made with continuous filament fiber (Lamilite) as we make them here at Wiggy’s it would not have retained any of the moisture. I guess the claim that these polyester balls mimic down is accurate since the Thermoballs trap the moisture as assuredly as down absorbs the moisture.

They insert the balls into triangular shaped baffles, a baffle structure used for years in the manufacture of sleeping bags, but they are making them smaller; I quote”Triangular baffles aren’t new, but the ones in the Thermoball jackets are smaller than any it’s been possible to use with down, since the individual balls in Thermoballs are smaller than each down feather”. If this is the case then the overall loft can’t be very much. They do not give a temperature rating for the jacket, I quote what they do say “ThermoBall weights about the same as down, but TNF claims its ratio of weight to warmth is 15 percent better than the best synthetic material, even though by specific clo ratings (the rating used to measure thermal insulation), down is still superior”. This statement is further proof of the lack of knowledge of insulations by the people employed at TNF. Ounce for ounce continuous filament fiberfill is not only the most efficient synthetic insulating material in the world, but as I said before it even makes down obsolete. The claim of 15 percent better is a fictitious number pulled from thin air, and if the ThermoBall is so good why at the same weight and thickness wouldn’t is be equal or even superior to down? They can’t say that because that would mean that a synthetic is as good as down for warmth but superior because it is not affected by water. Actually this construction will hold water in the garment. In my opinion, from what I have seen, from all of the companies that make outerwear or sleeping bags they just say what ever they think will sway the consumer towards their product. So, TNF is not alone when it comes to presenting erroneous information about their products.

Unfortunately TNF will sell these jackets to the general public who will never use the garments beyond the movie theatre, so it will not matter that they are ill suited for cold weather climbing as far as I am concerned.

Once TNF gets this product out there I would not be surprised if they start showing sleeping bags with these balls inserted. If that does occur I can’t imagine how false the temperature ratings will be.