When I had my retail store in 2000 - 2002, I had to explain to every customer what latex foam was – yes, it can be natural, yes, it comes from a tree, no there isn’t an allergy risk, yes, it will last longer than most mattress materials. These days, everyone is an “expert” on latex and we tackle a new list of questions and issues. Over the years, I’ve heard many crazy tales about latex. Manufacturers claiming proprietary “powdered” latex, customers indoctrinated in Talalay or Dunlop, latex “memory foam” products. It’s hard for those of us in the industry to keep up, let alone consumers. Here are just a few common questions, we hear over and over.
- What’s the difference between Talalay and Dunlop?
- Is it organic? What does that mean?
- Are there allergy risks? What about off-gassing?
- What does blended latex contain?
- Does it “really” last longer than memory foam? Is there latex memory foam?
In order to tackle these questions for consumers, it raises a few new ones for the manufacturer:
- Is latex foam still an excellent choice for mattresses?
- How much has each process evolved?
- Which certifications really matter?
- What’s the environmental impact of rubber trees?
- Will increased demand create new environmental issues?
In this blog series, I will start to unravel the many unanswered questions and tackle the tall tales about latex rubber, starting with a little background on the revolutionary commodity, then the health concerns that so often enter the equation, and finally the environmental impacts of increasing demand.
Latex: A Short History
This story begins in the early 19th Century, when the vulcanization process - making rubber or similar polymers into a more durable material using sulphur - was invented to stabilize the rubber by using sulphur. Although rubber has been used for centuries, dating all the way back to the Maya & Aztecs for their rubber balls, it wasn’t until vulcanization techniques were employed that it made it’s industrial debut. This discovery led to increased uses for rubber and as a result, plantations were planted in the most tropical regions of the world. Rubber plantations were replacing rainforests at an alarming rate. natives were forced to work in the plantations, tapping trees and collecting this new found “liquid gold”. While the rubber tree was native to Brazil(hence the name Hevea Brasiliensis) it was quickly transported to other tropical climates, most notably Southeast Asia, Southern India, and Southern China. Rubber is arguably one of the 3 most important raw materials to humankind in the world. Without natural latex, we would not be able to fly in airplanes, drive cars, make shoes, or have the myriad medical supplies our hospitals rely on today. The list of products using rubber components is more extensive than most can imagine, including mattresses and pillows.
So why exactly does this matter? Well, it’s important to understand where we’ve been, to know where we are going. Rubber has become such an important raw material in a relatively short time, and technologies are constantly evolving. When I started my business over a decade ago, we had only two options for latex foam: Dunlop or Talalay processed foam. We now have more high-tech versions of Dunlop with the addition of continuous poured Dunlop latex foam, slow release latex blends, and the Talalay process gaining attention as the preferred choice for consistency and quality in latex foam. To further our choices, we have an organic standard designed specifically for latex that certifies the plantation and process. To help you as a consumer wade through the jargon, here is a primer on these new choices.
Dunlop and Continuous Pour Dunlop vs. Talalay
Dunlop Latex is the oldest method for molding latex into foam - invented in 1929. There are many facilities that make Dunlop latex, typically in the country of origin. Think about making a cake. First you have your wet ingredients (latex & soap) and then the dry ingredients (vulcanizing accelerators), which are mixed together. These are whipped up into a froth in a centrifuge and then poured into a giant pan. This pan has pins sticking up throughout that heat up to make an evenly cooked core (these pins create the holes in the latex). Then a lid is put over the pan, it’s pressurized and baked. Finally it’s rinsed and dried and ready to ship. Dunlop accounts for the vast majority of the all natural latex foam.
In the Continuous Pour Dunlop facilities, this all happens on a conveyor belt with moving pans being filled and baked continuously. Continuous Pour uses infrared technology for even baking. This process can also forgo the pins and pour thinner latex sheets to create rolls for quilt-backing and toppers.* There are a couple of facilities in the United States and the majority of this latex is a synthetic latex blend, however natural latex is now being made as recently as last year with increased demand.
Talalay is the most high tech process and was developed in the 1940’s adding a few key steps to the Dunlop method. There are only a small number of plants worldwide that produce Talalay Latex - one being in Connecticut and the rest overseas. There are 2 key differences between Talalay and Dunlop. 1. The process employs a vacuum to evenly distribute the latex solids in the mold. 2. It flash freezes the mixture, suspending the particles throughout. This method gives an airy, soft feel to the latex and minimizes the settling of solids to the bottom. The majority of Talalay is synthetic rubber and/or a blend of natural and synthetic, however Natural Talalay is available. Talalay latex is more costly than Dunlop and is usually relegated to the top comfort layers rather than support layers given it’s softer, springy feel.
* One often misrepresented fact about latex is the holes make it breathable. Latex is actually an open cell material that naturally breathes. The holes can change the feel of the foam - firmer or softer with bigger and smaller holes.