"Japan's Top Inventions"

The behind-the-scenes tales of hit products and creations from Japan.

This is "Japan's Top Inventions."

On today's show, a water filter.

It's effective enough to turn this orange juice clear.

We'll share how it was invented.

Wow, that's a big one!

Later on the show, this device.

Turn the wheel, and the part in the center moves.

Just what is it for? Stay tuned to find out.

Hello. Welcome to "Japan's Top Inventions."

I'm your host, Jason Danielson.

In the first half of the show, we take you "Behind the Creation."

Today's topic is this.

Home water purifiers.

The one shown here attaches to your tap.

The device has a filter inside which removes bacteria or rust,

which may be in the water.

In addition to Japan, these home water purifiers have been used

in over 50 countries and regions around the world.

It was developed by a major textile manufacturer.

A special cafe in Tokyo.

Over in this corner,

you'll find the latest home water purifiers.

In fact, this cafe is also a showroom

for a major water purifier manufacturer.

There are models which show the remaining filter capacity...

and jugs that you can fill up and keep in the fridge.

These purifiers make use of something called a hollow fiber membrane.

The surface of these white fibers is full of tiny holes

which capture bacteria and particles.

Our story begins back in 1983.

After World War II,

the water infrastructure across Japan underwent much development,

and more people had access to tap water than ever before.

Whether it was for drinking or cooking,

tap water became an integral part of daily life.

At the time, there was a major textile manufacturer

developing products in Aichi Prefecture.

A new product was being worked on here.

It was a portable water purifier, which you could take on trips overseas.

Development started after the company president took a business trip to Mexico.

There, he'd fallen ill after drinking some of the local water.

At the company developing purifiers now is Takeda Hatsumi.

Here's what she heard about those times.

Many countries didn't have the same access to clean water as Japan.

The order was put out to quickly form a team

and make a portable water purifier to address this.

And so, development started on the portable water purifier.

The development team began coming up with ideas.

A portable water purifier which could be taken on trips overseas.

First, the team researched what drinking water was like around the world.

Some areas did not remove unwanted odors from the water.

That was something to address.

How could the odors be removed?

The team found something promising.

Activated carbon,

which was used in water purifiers made by other companies.

The surface of the carbon has many pores,

which capture the particles causing odors.

At the time, water purifiers relied only on activated carbon.

But another issue was bacteria in the water.

The size of the bacteria didn't match the pores in the activated carbon,

so they didn't get caught.

Bacteria aren't caught by activated carbon.

The size of the pores isn't right for catching them.

The bacteria slip through the layer of activated carbon and end up in the water.

How could the bacteria be removed?

The team decided to use a certain something.

Their company was the first in the world to create a special thread.

It's known as a hollow fiber membrane.

At a glance, it looks like ordinary white thread.

But if we magnify,

we can see how it's composed of hollow tubes.

Zoom in even further on the surface,

and you'll find countless holes about 0.1 micrometers wide.

Bacteria are caught in these holes when the liquid passes through.

Hollow fiber membrane filters are used during surgeries

requiring cardiopulmonary bypass in the blood oxygenators.

Could this technology be used for a portable water purifier?

The team moved to create a prototype.

First, they added activated carbon into a tube for removing odors.

Then they bundled some hollow fiber membrane on top.

The idea was to place this filter unit inside a water bottle.

But that was when they ran into a problem.

How would they get water to pass through the filter?

Without some kind of pressure, the water would not go through.

The pores of a hollow fiber membrane are very small.

You need pressure in order to push the water through.

A lot of testing would be needed to find something that would work.

The team needed a way to add pressure.

They kept searching, but no promising ideas were coming up.

Development had hit a wall.

The team had thought of using hollow fiber membranes for a water filter.

Nothing like it had been made yet.

The developers were struggling to come up with a solution to their problem,

but that was when they found inspiration from an unexpected source.

How could the water be forced through the filter?

The team continued to search for an answer.

One day...

There was another part of the company which worked on medical devices.

A certain component caught their eye,

the bulb on a blood pressure monitor.

Straightaway, they put together a prototype incorporating a bulb.

For testing, they headed for a small pond within the company grounds.

A member took a sample.

The water was green.

The pond water was placed in the prototype.

The lid was secured, and they began pumping.

The water coming out was clear.

Bringing the sample closer, they noticed no odors.

But the problem would be the bacteria.

The team members downed their glasses

hoping that the hollow fiber membrane filter had captured the germs.

The next morning.

The team assembled at the office.

Had anyone fallen ill after drinking the water?

Everyone reported that they had been fine.

And so, in April of 1984,

the world's first portable water purifier

with a hollow fiber membrane filter was complete.

Around the time the portable water purifier went on sale,

a certain report was making the rounds in Japan.

"Tap water has been tasting mustier lately."

The reason was said to be an issue with the river water.

Wastewater and runoff entering the source was causing algae to bloom.

There was demand for purifiers for tap water as well.

The team began coming up with designs.

Their idea?

A pot which connected to the faucet with an attachment.

The pot unit contained the filter.

There was no bulb, only a direct connection to the faucet.

The idea was for the pressure from the tap to push the water through the filter,

removing bacteria and odors.

However, a team member pointed out a problem.

"Can we really just connect it to the faucet?"

"Different homes have different water pressure."

The tap water in regular households is pumped from the water treatment plant.

That means that places which are closer to the plant have higher water pressure.

Their water comes out nice and strong.

But places which are far away have weaker water pressure.

The team took their prototype with them to a 14-story apartment complex nearby.

A tank on the roof supplied water to each floor.

The lower floors have the highest water pressure,

while pressure is lowest on the highest floors.

The team spent day after day knocking on doors

and asking for help with testing.

They tested the water pressure on each floor, from 1 to 14,

all the while making improvements to their prototype.

They tested in actual kitchens,

and checked whether the amount of water coming out was good or not.

It was very hands-on.

September 1984.

Finally, the home water purifier was complete.

To market their new device,

the sales team invited representatives from retailers for a demonstration.

And at the front of the room?

A tank full of goldfish.

It was a memorable stunt.

Purifying fish tank water and drinking it.

They wanted to prove it worked, that the water would come out clean.

It was time for the demonstration.

The fish tank water was poured in.

The purifier went to work.

Was the water truly clean?

The retailers who were watching were amazed.

It was quite the sight, and conveyed how effective the purifier was.

The team thought of that product like their own child,

and it was like it was all grown up now.

I think they were overjoyed at the reception.

And so, the home water purifier was revealed to the public.

Its reputation continued to grow,

and production ramped up to meet the high demand.

Today, home water purifiers are common all over.

How do experts view this invention?

We're joined by Tanioka Akihiko to learn more.

Welcome to the show.

Thank you.

What was significant about the first home water purifier to use hollow fiber membranes?

Hollow fiber membranes have pores

which are the right size for catching bacteria,

including microbes which attack the gut,

which are especially difficult to remove.

Purifiers which use these filters are considered very safe.

How common are Japanese home water purifiers around the world?

Water quality is different around the world.

Purifiers which use something called reverse osmosis are common.

These can catch smaller particles compared to hollow fiber membranes.

They're used when heavy metals such as arsenic are in the water.

Japanese reverse osmosis filters are in use in a number of countries.

What is Japan's role in helping to provide safe water around the world?

There's a movement worldwide to make wastewater fit for drinking again.

Singapore was the first to do it,

but the US has been making an effort to explore this option lately.

Japan has the technology for making various membranes

used for processes like reverse osmosis.

I hope to see Japan make use of its knowledge

to help make a difference around the world.

Thanks for your time today. Good speaking with you.

Thank you.

Top Niche Creations.

Our next segment is "Top Niche Creations."

Today we're talking about these,

components with red handles and wheels.

They're actually industrial valves made with plastic.

Turn the handle and the member inside moves to block or let fluid through.

Metal valves are common, but plastic ones have strengths of their own.

Plastic valves are currently being used all around the world.

What's special about these valves?

We sent our reporter to find out.

Hello everyone, Cyrus Nozomu Sethna here.

Today I am in Miyazaki Prefecture in southern Japan.

The company we're visiting is in this building over here.

Come join me!

The factory of a valve manufacturer in Nobeoka, Miyazaki Prefecture.

Good afternoon.

Hello. Welcome.

Showing us around today is engineer Kosho Kenji.

Stepping inside...

Oh wow. You got valves of all sizes here, big ones and small ones.

- That's right.
- Nice.

The most common type is around 20 centimeters long.

It's lighter than metal, right?

Much lighter.

So it's easy to carry.

Yes. Up to a certain size, you could carry it around by hand.

These are the smallest models.

Wow, this one's really tiny.

Yes, this is our smallest one.

6-millimeter diameter.

On the other hand...

Now that's a big one.

What's the diameter on this?

That's 900 millimeters.

Amazing. Nearly 1 meter wide.

That's right.

It's not only the size that's different,

but the components as well.

In the center is the gate which blocks the fluid.

Moving this is how the valve controls the flow.

Just how does it move?

I got a chance to operate it.

There we go. It's started moving.

After spinning the wheel for about a minute,

the valve is completely opened.

There's also this type.

Just rotate the handle,

and the part inside moves.

What's in there?

So, inside, you have a round gate like this.

Moving this 90 degrees opens and closes the valve.

It's simple, but effective. Very neat.

Valves with many different sizes and gates.

And they're all made of plastic.

Metal valves are common, so why make ones out of plastic?

I asked Kosho to learn more.

Our customers operate chemical plants

which handle fluids like sulfuric acid or hydrochloric acid.

If the valves were made of metal, they would corrode.

Right.

Iron rusts, so we make valves out of plastic

which don't have the same weaknesses.

That makes sense.

For example, this factory does metal plating.

As part of the process, hydrochloric acid is used.

Because of this, the factory uses plastic valves which don't corrode or rust.

Plastic valves are even used here.

This large aquarium is full of salt water.

To prevent the piping from rusting, this system also uses plastic valves.

Currently, this company holds a large share

of the domestic market for these valves.

It was founded in 1945.

Originally, it made black plastic bodies for telephones.

But later, in 1956,

it decided to address the issue of corroding metal valves,

and developed plastic valves.

There was however, a key challenge with durability.

In terms of absolutes, metal is stronger than plastic.

The early valves that went out were weaker,

and so we had to keep iterating and improving on the design.

The development team back then updated the design of the valves,

and increased the thickness of the body.

They experimented repeatedly to make the valves stronger, bit by bit.

This is footage of employees carrying out a durability test.

Even after dropping the valve 5 meters...

it's totally fine.

Even with a 3-ton forklift driving over one...

as you can see, it remains intact.

And now, the company's valves are being used in a new field.

We're shown the latest models.

These are valves used inside cleaning devices for semiconductors.

Amazing. They look totally different from the other valves.

Yes. This valve has a piston which moves up to control the gate.

When the piston rises, the gate opens and the water flows.

Semiconductors, a key part of electronics, computers, and smartphones.

As part of the manufacturing process, the base material must be cleaned.

A kind of ultrapure water is used for cleaning.

The company's plastic valves control the flow of this water.

There's a reason why the valves are white.

So, why white?

It's a plastic known as PTFE,

also used for nonstick coatings.

That's what it's made from.

This PTFE doesn't add impurities into the water.

If the valve itself introduces impurities,

that would lower the manufacturing yield.

So even though the fluid is just water,

you need plastic valves like these.

Leave it all to the valves, huh?

Yes. Well, valves are a bit of a niche product.

We're hoping to support industry with our offerings.

A key benefit of plastic valves is that they don't rust.

Just how resistant are they?

This experiment compares metal and plastic in beakers of hydrochloric acid.

The effect over time is obvious.

The metal has corroded, but there is no change to the plastic.

Plastic valves which don't rust.

These humble components are helping factories

to operate smoothly all around the world.

That's all for this episode of "Japan's Top Inventions."

We'll leave you with more about the home water purifier

from the first half of the show.

See you next time! And Stay Inventive.

(It's been over 35 years since that first home water purifier.)

(Since then, they've come out with a compact model for the tap.)

(The purifiers helped create a new market category.)

(Hollow fiber membranes are used for the filter.)

(These membranes are also being used with industrial wastewater.)

(Takeda helps develop the home water purifiers.)

(She feels inspired whenever she sees the original model.)

The concept our predecessors put out was widely accepted.

I believe taking a big leap like that is something any generation

at any time can learn from.