STEM Nibbles
September 3, 2021

Printed Edible Chocolates – When are they coming?

You must have printed a lot of things on paper, maybe even on plastic and cloth. Printed materials surround us everywhere and at all times! Whether it is the family photos at home, documents in office, boarding passes on our holidays or the menu card at our favourite restaurant.

Now imagine that you wanted to have your favourite dish from that menu but the restaurant has run out of all the cutlery. What could you possibly do? Walk over to the special printer kept on the corner table and simply print out a real fork and knife? Does that sound like magic? Well, as Sir Arther C Clarke famously said – “Any sufficiently advanced technology can be called magic”. The advanced technology that we are talking about here is known as 3D printing!

What is 3D printing?

3D printing or ‘additive manufacturing’ is the technology that helps to construct 3 dimensional (3D) objects using Computer-Aided Design (CAD). It is currently one of the fastest-growing methods in the world of architecture and manufacturing. But first, let’s go back about 40 years to know about how it all started and how it works.

3D printing How it all started – a 40 years old story

It was way back in 1981 when one of the earliest inventions in 3D printing happened by chance. A scientist named Hideo Kodama, in Japan, realized that he could harden plastic models almost instantly (based on temperature of the surroundings) by using a specific kind of viscous liquid known as the thermosets. Thermoset is a material that hardens when it is heated. But, once strengthened it cannot be heated again to reshape or remould it.

However, the real breakthrough happened almost 3 years later in 1984 when an American named Bill Master, discovered and patented the way to make these models by giving the instructions to the printer using a computer. This allowed the manufacturing to happen in large quantities (bulk) and laid the foundation of 3D printing.

How do 3D printers work?

Let’s take a simple analogy to understand the process. Imagine that you have a paper cone filled with sand. Now if you cut the cone at the pointed end, the sand will start to pour out. If you move the cone, it will leave a trail of sand along the path. However, the grainy nature of the sand particles will not allow them to form layers and we will end up with just a trail of sand dunes.

But, now imagine what would happen if you used a material that can stay on top of each other as fixed layers? All these layers would stack up and form a 3D shape! This method of stacking materials, layer by layer, to form 3D shapes is known as Stereolithography. The 3D printer prints by layering a design from the base and stacking up all the layers till the top.

Thus, stereolithography is possible only with materials that can be deposited, joined, or solidified easily. Hence, materials such as plastics, liquids, or even powder grains fused together are some of the good material choices.

Current status of 3D printing

In the initial days, 3D printing was limited to making small prototypes of objects/ machines only. So, this earned it the name Rapid Prototyping Technology. But it has progressed rapidly in the last 40 years. Today, 3D printing technology is one of the most promising manufacturing technologies of the next decade.

Besides manufacturing, it could help us to solve critical issues such as environment-friendly products, world food crisis, and global warming.

Researchers are looking at extracting the carbon dioxide gas (main culprit for global warming) in the air and converting it into concrete using 3D printing technology.

Many modern-day 3D printers can even construct small houses (about 800 square feet) within a day.

3D printing has also found its way into the world of medicine. Now, surgeons use 3D printed models of body parts (using the data obtained from CT scans) to plan for the real surgery. From prosthetics (artificial limbs) to custom bone replacements, possibilities are infinite with this revolutionary technology.

A fully-functioning 12-meter steel bridge is the latest accomplishment of 3D printing technology. Installed in July 2021, the “MX3D bridge” is a fully working bridge weighing 4.9 tonnes of stainless steel, completely made using 3D printers and welding robots – something that would have been unimaginable even a decade ago!

Future of 3D printing Tech

3D-printing technology will transform how things will be built in the future. But every innovation has its own limitations. In this case, it the limited choice of materials available for “printing”. Temperature control and moulding at will are the 2 most important properties of these materials. This makes plastics and some metals as the most widely used materials choice for the 3D printed materials today. However, they cannot be recycled and very few are food grade.

However, the lack of technology today doesn’t make it impossible! That’s what researchers and scientists and engineers are there for! NASA is already exploring 3D printing as a technology solution to “make” food for the astronauts!

Maybe, one day, you will have a 3D printer neatly tucked away in the kitchen with buttons to print out real, edible chocolates and ice cream flavours for you! Maybe even sooner than you think! But will it taste the same and give you the same joy that you get when your parents get it as a surprise for you?! What do you think?!

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