Posted by Nancy Grossbart
The most interesting products can be made from the injection molded EVA foam process. The process was originally created to manufacture midsoles but over the last 20 years, it has become so much more. Even when we don't make the part, we love to see great design using our process.
My favorites this week are some of the latest designs from the footwear company, Native Shoes. (I also love fun shoes.) They are made 100% injection molded EVA foam; that means both the sole and the colorful uppers. EVA foam is closed cell which means they are washable, antimicrobial, and odor resistant. It is really lightweight which could be plus depending on where you're walking.
From a designer’s perspective, molded EVA foam can be ideal when a design needs to be expressed in really vibrant colors. The foam's ability to create saturated colors gives a designer the confidence to really "break out" when using this foam. Obviously, that's what makes Native Shoes so dynamic looking.
Whether you’re wearing the slip-on (one-third Vans and two-thirds Crocs) or the hiking boots, these shoes are really made for walking as the molded EVA foam will contour to your feet as the foam warms up, making them extra comfortable.
As far as I’m concerned it’s another fantastic design utilizing a process that I have grown to love. Visit our product gallery if you want to see some other fantastic designs.
I been looking on the web to buy the boots but they don't seem to be available yet. When they do become available, someone let me know so I can get a pair. Which color should I get? Hmmmmm.
Posted by Nancy Grossbart
I love this story, even if we didn't make the “One World” soccer ball.
This soccer ball took 5 years to develop. I can believe it. I, absolutely, know how hard this soccer ball was to manufacture. I've worked on lots projects in the injection foam molding process that have required extensive R&D to make the product come out just right.
It all started when a music producer and inventor, Tim Jahnigen, saw how children traumatized by their violent environment “were desperate to play with anything.” It gave him the idea to create an indestructible soccer ball.
After 5 years of development, and some help from Sting, he developed a soccer ball with the injection foam molding process like Crocs sandals.
The soccer ball is indestructible because this soft foam is basically indestructible. How long have you worn your Crocs sandals? The soft foam has its own, extremely durable, skin that is formed during the manufacturing process. Inside the skin is an equally tough, closed cell, foam that won’t absorb liquid.
See how a truck can run over it and still not destroy it.
All of these process and foam benefits mean the kids will be able play with this ball in any environment with no chance of it being flattened, and almost no chance of it ever being damaged. I understand a ball was given to a lion in the Johannesburg zoo. Even he couldn’t destroy it.
You can learn more about it in an article in the San Francisco Chronicle.
Posted by Nancy Grossbart
Almost any resin can be foamed. The world of foam is made from many different resins yet the injection molded foam process uses EVA, in combination with polyolefin elastomers. Why is that? Because it makes soft foam parts!
Hard or Soft Foam? There are many other polymers like polypropylene, polyethylene, or polystyrene which can easily be foamed creating a lower density, lighter product. However the results will stiff and hard as they are hard and stiff resins to begin with.
EVA produces flexible foam. EVA is a polymer that is similar to an elastomer because it can be made to be soft and flexible. That's the origin of the term flexible foam. This means that when soft EVA is manufactured, the resulting foam will also be even softer and pliable, allowing the production of varied soft foam parts to be used in industries such as juvenile, outdoor, sporting goods, kitchen and bath to name a few.
How does it work? In a simplistic sense, any formula combining EVA and polyolefins will have a linear chemical makeup. Under normal circumstances, having a linear chain creates a harder material. However, because of the specific chemical makeup of EVA it won't crystallize easily, helping it to retain its softness. In addition, EVA foam can be crosslinked, which will both help to stabilize the foam as well as produce soft foam final parts.
Crosslinking creates stable soft foam. Basically crosslinked foams, like EVA foam, are more stable than similar highly expanded un-crosslinked foams. This means it can retain its foam structure at temperatures approaching the melting point of the polymer used and, in some cases, exceed it. One of the additional benefits of parts made from EVA foam, and other crosslinked foams, is the ability to create parts by compression molding methods, including the injection molded foam process.
Why EVA foam is a perfect resin for our injection molding manufacturing process? It produces soft EVA molded parts that are stable, durable, closed cell, and chemically resistant.
Learn more about "Understanding Injection Molded Flexible Foam". Download our 8-page white paper.
Posted by Nancy Grossbart
5 ways products manufactured by injection molded foam differ from compression molded foam, not counting the obvious...Injection molded foam products are made by a pellet to product process, injecting a melted pellet into a closed mold foaming the formula into a multi-dimensional design. Compression molding foam can't come close to creating the same complex designs. However, when injection molding produces the same, or similar, product to compression molding here's how they differ.
Aesthetic Quality. When it comes to a finished look, the overall appearance of a compression molded (vacuform/thermoform) foam part cannot compare with that of an injection molded foam part. The increased density, and perfect "mold" finish of an injection mold, produces a part with far superior aesthetics. Because the foam used for compression molded parts is outsourced, the quality of the foam is also likely to be variable, affecting the final aesthetics of the part. On the other hand, because the injection molded foam is manufactured in-house with the foam and part made simultaneously, the quality is always consistent.
Specific variables that affect quality in compression parts, but not injection parts, are:
- inconsistent cell count within the foam, variable pigmentation and density in the raw materials causing color variation
- inconsisent part to part processing time, temperature and degree of compression causing variation in part definition.
Dimension Quality: The ability to produce a consistent dimensional part is based on how well the molding process can be controlled. The pellet to product process means that the manufacturing of the foam, and final part, are one and the same. Most processing conditions can be controlled and duplicated, resulting in minimal part to part variation. Compression molding, however, starts with a bun or sheet of foam that is heated and molded into a different shape, subject to far more variable processing conditions. In addition, the need for final trimming of the compression molded part can also be a major contributor to a low quality image.
Thickness Variation: If the final product has varying height profiles, a compression molded part must start with a sheet (bun) of foam that is the height of the tallest dimension of the part. If the foam chosen for the compression molding process does not come in a thick enough bun, laminating sheets together is required to form thicker buns. This can result in that some parts have a lamination line which can delaminate with time. Injection molded foam parts, however, can be made to any height, not limited by the process, without need for lamination.
Post Mold Stability: Another area where the two processes differ significantly is what happens to the part after it is processed. Injection molded parts are extremely soft and malleable when they finish their molding cycle. During the post molding phase, a cooling fixture may be required to help the part maintain its shape. Unless the part is subjected to external forces that causes it to change shape, the final cooled part will be exactly what was expect. On the other hand, compression molded foam parts can suffer post molding shrinkage and warp, even if cooling fixtures are utilized.
Cost and Value: Compression molded foam parts will almost always cost less than injection molded foam parts. Not only is the tooling and manufacturing equipment less expensive but the parts as well. Because compression molding uses bun stock, low density (inexpensive) foams are often chosen. This results in lower quality products that are great for a give-away or other temporary product. Injection molded foam products, while more expensive, are attractive, with long lasting value.
Both compression molded foam and injection molded foam have their place in the world of manufacturing. Choose the foam process that is best for your product.
Posted by Nancy Grossbart
Lately, I find myself waxing philosophical about great product design and what it really means. I voraciously devour articles and blogs on the subject, finding that the writings that affect some inner space inside me are the ones that make the most sense. Knowing great product design is probably more emotional than anything else.
Dan Harden's article at Fastcompany.com about the Disappearing Act of Good Design affected me that way. In his blog, he says.
When a product is so completely and rightly designed, it has aesthetic and functional elements that are clearly stated and obvious. The product itself communicates without words its utilitarian value, ease of use, and beauty, and you perceive the quality-contributing elements instantly.... When a product does all the above things well, instead of it having abundant presence like one would expect, it actually sort of disappears when you use it.
What this means to me is the best product designs are ones you love instantly and then take for granted (in a good way) after you incorporate them into your everyday life. Harden uses the examples of the iPhone, a Porsche, an Aeron Chair. All of these are great designs that we admire whether we own one or not.
As a manufacturer of injection molded polyolefin and EVA foam, we have worked with some really great product developers and product designers. One customer, in particular, made the development process extremely difficult by creating five different designs (five molds) over a two to three year period before settling on the final design. As you can imagine, from a manufacturer's perspective, we were both frustrated with the process and anxious to be in production. However, when the 5th design came out of the mold, it was astoundingly beautiful both in aesthetics and function. It was hard to remember ever being frustrated, which only emphasizes Harden's take on this.
There is unity and wholeness, and it is so evident that this thing will totally satisfy a physical and/or emotional need....The product becomes a subconsciously satisfying experience, not a heavy conscious thing that demands attention because it's pretty or different...
I recently heard a story about Holly Hunter, the Academy Award Winning Actress, who is starring in the TV series "Saving Grace". One of the directors is a friend of a friend. The director said "She is so frustrating. I have a budget to meet and every time I OK a scene, ready to move on, Holly always asks for one more take insisting that she can do it better. Reluctantly, I agree and every time she is right. She adds that something extra that makes it amazing."
Obviously, this doesn't relate directly to product design or molded foam or foam manufacturing. It does, however, relate to the truth that when creativity is right, it's just right.
Posted by Nancy Grossbart
When I went on an interview for a marketing job at a TV station, early in my career, I was asked that age-old question "What are your five-year goals?" I sat there very quietly, not answering, for way longer than was comfortable for either of us. I kept thinking what are my five year goals...what about three year...do I even have one year goals? Tick..tick..tick. What am I going to answer?
Finally, the silence was so long, so pregnant, I blurted out this long stream-of -consciousness mind-dump, "I have no goals. Well, it's not that I really have no goals. It's that my goals are always changing as I get more experience and I don't want to create a goal for something that, six months from now, I will change my mind about."
The interviewer sat looking at me as if she had never heard anything like it before.I stared back nervously thinking I had totally screwed up my chances for this job but couldn't make up goals I didn't have. Finally, she said, "I like that answer because that's how life really works. You're hired!"
Well, that's not exactly how it happened. There was a lot more discussion before the "you're hired" part actually happened. What was most important is that I got the job because she really understood how I saw the concept of goals.
When I think about it, it's very similar to the creative process. You start your product development cycle with set goals that must be met. However, when you're actually involved in the product design itself, you can start with one concept that takes you to the next, and then the next and the one after that. And when it is all over, you end up in a place that you love, but never expected.
Look at me. I ended up in business development at an injection molded foam company. It really goes to prove that life is a creative adventure, one creation after another.
Posted by Nancy Grossbart
Part of my daily web meanderings take me down the path of looking at new product designs and concepts. If you follow me on Twitter (@foamentingideas) you will see that I am apt to share these "finds." Yesterday I came across a unique bathroom tile with the towel hook built in. 
It was designed by Czech designer Vadim Kibardin. I liked it immediately as it was both innovative and very practical. How many times have you been in the shower and wish you had easy access to a towel? It's a thoughtful, beautiful design as is but (being in the foam business) I suddenly realized "this design could have been made of injection molded foam."
I know this sounds like a commercial but, I swear, it's not. Don't you agree that foam tiles on the shower walls wouldn't be a great idea?
Imagine it could be both colorful and protective at the same time. Because this foam is closed cell it wouldn't absorb any of the water. Plus the base resin is chemically resistant, allowing you to keep it clean with any regular household cleaner.You could even mold logos and textures into it.
I will probably come across lots of products that fit the "It Could Have Been Made From Foam" description. When I find them, I'll talk about them. If it feels like a commercial then I'll, at least, try to make it a commercial worth watching.
Posted by Nancy Grossbart
When my company (MDI Products) first began to work with product designers who wanted to create a foam product and had lots of plastic molding experience, it was very difficult to get them to "think differently" about how to design a product that took advantage of our
injection molded foam process. There are only some things about both processes that are similar. Both plasticize raw materials in a hot barrel. Both inject in the materials into a closed mold. Pretty much the similarity stops there.
Understanding the fundamentals is key to designing a great part. To really comprehend what is happening, you need to first know that injection molded foam is actually a foam manufacturing process which manufactures foam in the shape of your part.
The next area to understand that, unlike the single mold plastic process, the machines used in the injection molded foam process are multi-station presses, which utilize multi-molds.
Again, unlike plastic injection, the mold cavities are designed smaller than the final part size. The parts expand rather than shrink. The amount of expansion is dependant on the material softness you require.
The material remains in the heated mold during the cross-linking or cooking process. The cooking time is dependent on the thickness of the part. The mold opens very quickly when the cooking is complete. The part expands and explosively self ejects from the mold cavity. The part is removed from the mold station and set to cool.
Learn more about self-ejection, draft, corners, edges, and undercuts later.
Posted by Nancy Grossbart
Polyolefin foam is a great material for kid's products. It works well in lots of applications from padding for sporting goods to sandals (Crocs) and now, products for kids.
To begin with, it's closed-cell. That means it's waterproof and won't absorb bodily fluids. It also means it resists mold and mildew because the bacteria has no place to reside.
It's so light that it floats and can be used for bath or pool toys and has no adverse chemicals so when kids put the toy in their mouths, there is no need to worry.
Polyolefin foam has a high tear and tensile strength so it can't easily rip and won't crack or peel. This means it will not only last a long time but, when kids put it in their mouths, it will pass the bite test.
The chemistry of polyolefin foam makes it resistant to most chemicals. This allows you to clean and disinfect it with any household cleaner keeping it safe from any surface bacteria.
Parts can be also designed with lots of features and benefits including molded-in logos and graphics. And can be made in extremely bright, attractive to kids, colors.
If you're wondering if it will pass the new CPSIA standards, it will!
MDI Products' offering of formulas known as PolyCellTM are phthalate free, PVC free, AZO dye free, with insignificant metal content. In addition to all the other reasons why it is great for kid's products, you can also be confident of its safety.
I'd love to get your feedback on what other specifications might be important for kid's products.
Download 8-page white paper on
"Understanding Flexible Foam".