Mosquito Coils / Screw Removal Tools

The fascinating stories and secrets behind hit Japanese products, plus parts and machines that boast the top share of niche markets. In the first half: the story behind mosquito coils, invented by a Japanese company, which help prevent mosquito-borne diseases around the world. In the second half: we introduce screw removal tools that can remove stripped screws when a normal screwdriver can't.

Ueyama Hisashi, involved with the development of mosquito coils
Takasaki Mitsuhiro, involved with the development of screw removal tools
The tool that can remove a screw by tightly gripping the screwhead

Transcript

00:09

"Japan's Top Inventions"

00:18

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

00:22

This is "Japan's Top Inventions."

00:30

This time, a repellent for those blood-sucking mosquitoes!

00:35

We discover the unusual inspiration behind this coiled invention.

00:44

Meanwhile, check out this screw.

00:46

It's been stripped, so a screwdriver is no use.

00:51

We'll introduce a top invention that makes it easy to remove!

01:02

Hello, welcome to "Japan's Top Inventions."

01:05

I'm your host, Jason Danielson.

01:07

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

01:11

Today's topic is this.

01:14

Mosquito coils, a common sight during the summer in Japan for over 130 years.

01:20

Light the coil of incense, and watch the smoke rise.

01:24

The insecticide in the smoke knocks out any nearby mosquitoes.

01:28

These coils are used around the world,

01:30

offering protection against mosquito-borne diseases

01:33

like malaria or dengue fever.

01:36

How were they invented? It all started with a certain white flower.

01:43

Arida, a city in Wakayama Prefecture, west Japan.

01:50

It's home to a statue of a certain individual.

01:56

Ueyama Eiichiro.

01:58

Some 130 years ago, he invented mosquito coils.

02:05

His birth home, which still stands,

02:08

is now home to important artifacts from that time.

02:16

This is the machine used for creating mosquito coils.

02:21

Here, kneaded materials were pressed into stick form.

02:28

This wooden mold was used to fix prototype coils into shape.

02:35

This is where that iconic spiral, still used today, was born.

02:43

Our story begins in 1885.

02:47

With its warm climate,

02:49

Wakayama was known as a large producer of "mikan" oranges.

02:55

Ueyama Eiichiro was the owner of a long-running mikan farm.

03:03

He founded a firm to export mikan abroad.

03:06

His idea was to sell his fruits worldwide.

03:11

Ueyama's great-grandson, Ueyama Hisashi,

03:15

works as an executive at a maker of insect repellent.

03:19

He describes his great-grandfather's time.

03:24

It was the Meiji Period.

03:25

Japan had opened up and was determined to start its own industries,

03:29

and even export, to keep up with the West.

03:33

Since he was a mikan farmer, he decided to join in by exporting his own mikan.

03:39

That was his goal.

03:42

One day, Ueyama had a chance to speak

03:45

with the president of an American plant company.

03:50

Ueyama gave him a mikan sapling.

03:54

In return, he received seeds for a flower not seen in Japan.

04:01

Pyrethrum.

04:04

The flower is native to what is now Serbia, in Europe.

04:09

Its seeds contain a compound that acts as a natural insect repellent.

04:16

Pyrethrin, the compound that kills insects, comes out in seed form.

04:21

In Europe, it was mostly used as flea powder.

04:24

It had been gaining attention for some time.

04:30

Ueyama decided to start cultivating these flowers in Japan.

04:34

A valuable document he created himself remains.

04:41

A guide to growing the flowers.

04:47

It's said he traveled Japan giving lectures with this guide,

04:51

appealing to farmers nationwide.

04:55

Thereafter, cultivation expanded,

04:58

and its seeds were used as raw material to produce flea powder.

05:06

Its effectiveness led to its quick popularity.

05:13

One day, Ueyama ran into a farmer he knew on the street.

05:20

They started talking about the flea powder.

05:24

"It's working well," Ueyama was told.

05:27

"How about making a mosquito repellent next?"

05:33

To make rice, fields are flooded with water,

05:36

then seedlings are planted.

05:40

In summer, mosquitoes arrive in force.

05:43

Bites aren't just itchy,

05:45

they can spread a variety of diseases, leading to sickness.

05:52

Ueyama thought to himself,

05:54

creating a mosquito repellent would help not only farmers

05:58

but anyone worried about disease.

06:04

What's the insect that causes the most stress in Japan?

06:08

Even today, the answer is the same. Mosquitoes.

06:12

So he wondered if he could make something effective against them.

06:18

With that, Ueyama had his idea for a new product.

06:22

He quickly gathered some pyrethrum, as the raw material.

06:33

How to repel mosquitoes with these flowers?

06:37

Ueyama thought of "kayaribi," mosquito-repelling smoke,

06:41

long used in Japan.

06:45

Mugwort and other leaves were burned, releasing smoke to repel mosquitoes.

06:52

With this as inspiration, Ueyama turned to "hibachi,"

06:56

a kind of Japanese heater fueled by charcoal.

07:01

If he burned powder from the pyrethrum in one, would the smoke repel mosquitoes?

07:08

He tried it out, and...

07:14

A mosquito fell to the ground.

07:18

It worked!

07:23

I imagine he was thrilled. A triumphant feeling.

07:27

No one had seen that before.

07:29

Old mosquito smoke only chased them away. It didn't kill them.

07:34

But his did.

07:38

It must have been a terrific feeling

07:40

to be the first person to make a mosquito just drop like that!

07:44

I'm sure he was quite moved.

07:50

But his joy lasted just an instant.

07:53

He quickly realized something.

07:56

Mosquitoes mostly appear in summer.

08:00

You couldn't use a hibachi in that summer heat.

08:06

Was there another way?

08:08

Ueyama received inspiration from an unexpected source.

08:14

During a business trip to Tokyo, he shared a room with a certain man.

08:21

This man's family business was Buddhist altar incense sticks.

08:27

Many Japanese homes feature Buddhist altars.

08:33

Burned there are incense sticks.

08:38

Light the stick, and it releases a thin wisp of smoke.

08:46

"Eureka!" thought Ueyama.

08:50

He wondered if he could add pyrethrum powder to such sticks.

08:59

Returning to Wakayama, he added the powder to an incense stick as a prototype.

09:09

He lit it up, and...

09:19

A mosquito fell to the floor.

09:23

He wondered what would happen if he made it like an incense stick,

09:28

so he made a prototype using that know-how.

09:31

I think he was happy when he saw it work.

09:37

This is the first version of the product Ueyama sold.

09:43

After two years of development, it was released in 1890.

09:50

The world's first mosquito incense was not a coil,

09:54

but a straight stick.

09:59

After a great deal of trial and error,

10:01

the mosquito repelling incense was finally perfected.

10:04

At the time, three sticks would be burned to keep mosquitoes away.

10:09

But how did we go from sticks to a coil?

10:12

Well, there was actually a major issue with the stick form.

10:19

The product had been completed,

10:21

but these mosquito incense sticks were not widely adopted nationwide.

10:29

The problem was how long they burned.

10:32

A 20-centimeter stick burned for just 40 minutes before going out.

10:41

What about mosquitoes that came at night?

10:44

You'd have to wake up every 40 minutes to light new sticks!

10:48

And it's not like they had alarm clocks back then.

10:52

Who could do such an unwieldy task?

10:58

Ueyama tried making the sticks longer to increase their burning time.

11:03

However...

11:07

This was dangerous.

11:12

How to increase the burning time?

11:14

Ueyama pondered to himself.

11:19

One day, his wife Yuki called from the garden.

11:25

"There's a snake!"

11:30

Ueyama ran to the rescue.

11:35

In front of Yuki was a snake, all coiled up.

11:41

Yuki then said, "What about making the sticks coiled, like this snake?"

11:50

I'm not sure if she suggested it then and there, after being surprised by the snake.

11:55

But after receiving her idea, he made a prototype wooden mold,

12:00

which still remains.

12:03

He wrote her name on it,

12:05

to give her credit for coming up with the idea, I believe.

12:09

He wanted to give her credit for the ages.

12:14

Ueyama quickly prototyped a coiled version.

12:18

It was 60 centimeters, three times longer than the stick version.

12:25

But the problem was how to produce them.

12:28

Without the proper gap, the flame would jump the coil,

12:31

and it wouldn't burn till the end.

12:38

Alongside craftsmen, Ueyama tried various methods day after day.

12:46

Finally, they placed a stopper in the middle

12:49

and coiled two sticks at once.

12:53

This let them make two identical coils in one go.

13:01

Here's some rare footage of mosquito coils being made from about 70 years ago.

13:08

Skilled craftspeople could produce the coils from a long stick of incense

13:13

in just a few seconds.

13:20

However, just before the coils went on sale, another problem emerged.

13:25

The drying process.

13:30

When the coiled incense was dried on a board of wood...

13:43

it stuck to the board, cracking when peeled off.

13:50

Was there another way?

13:52

Ueyama racked his brain for an answer.

13:57

Again, it was his wife Yuki who had an idea.

14:03

"How about using wire mesh?"

14:08

Wire mesh, used for grilling fish.

14:11

Fish sticks to an iron pan.

14:15

But not to wire mesh.

14:21

Ueyama quickly grabbed some mesh and lined it with coils.

14:26

If they didn't peel off well, the coils could not be sold as a product.

14:35

Nervously, Ueyama waited for them to dry.

14:44

About five days passed.

14:50

Would the coils peel off cleanly?

14:56

Cautiously, Ueyama placed his hand on a coil.

15:16

It remained in shape, cleanly peeling off the mesh.

15:23

The adhesive surface was small, and because it was wire mesh,

15:28

there was some wind from below.

15:30

I think that helped reduce the moisture.

15:33

The mosquito coils were complete.

15:35

He must have been so thrilled to be able to sell them.

15:40

With that, the world's first mosquito coils were made available in 1902.

15:48

Even now, they are still manufactured in double coils,

15:52

and wire mesh is still used in the drying process.

15:59

And that was how the mosquito coils came to be mass produced.

16:03

Since then, the product has been used in many countries and regions around the world.

16:07

How do experts view this invention?

16:09

We spoke to Kasai Shinji, who researches insects that cause diseases.

16:15

Welcome to the show.

16:18

Thank you.

16:20

Can you tell me specifically what diseases mosquitoes carry?

16:25

In terms of mortality rate, it would be malaria.

16:29

Mosquitoes also spread dengue fever, chikungunya fever,

16:33

Zika virus, yellow fever, and so on.

16:36

The animals that cause the most deaths in the world aren't bears or sharks.

16:41

They're mosquitoes.

16:43

Mosquitoes are vectors for all these diseases,

16:46

so they pose a great threat to humans.

16:51

What would you say is the value of mosquito coils?

16:55

It's been over 130 years since their development.

16:59

I don't think there are many people that doubt the effectiveness of mosquito coils.

17:05

I often go on research trips to Southeast Asia,

17:08

and it's common to see the mosquito coils there.

17:13

So many people believe in the product, it's won their trust,

17:17

and its effectiveness is not under doubt.

17:22

That's quite a large contribution, I think.

17:28

What would you say about the relationship between humans and mosquitoes going forward?

17:34

There is climate change, which increases the number of places

17:38

where disease-carrying mosquitoes can live.

17:41

In Japan, we're seeing the range where Asian tiger mosquitoes are distributed

17:46

continue to move north.

17:49

So it doesn't look like mosquitoes are going anywhere,

17:52

and the problems associated with the diseases they carry

17:55

are also going to continue to be an issue.

17:58

Looking at all that,

18:00

I think humanity is still going to be fighting mosquitoes for a long while yet.

18:06

Thanks for joining us. Great speaking with you.

18:09

Thanks for having me.

18:13

"Top Niche Creations."

18:17

Our next segment is "Top Niche Creations."

18:20

This time, we're looking at these.

18:23

Stripped screws.

18:24

I'm sure many of us have tried in vain to get one of these out with a screwdriver.

18:29

A certain Japanese company looked for a way to deal with these troublesome screws.

18:33

We got a behind-the-scenes look at these special tools.

18:39

A tool maker in Osaka.

18:44

It's a small firm, with just 40 employees,

18:49

but a unique tool produced here is known worldwide.

18:57

This is our tool.

19:00

Just what kind of tool is it?

19:05

Developer and CEO Takasaki Mitsuhiro explains.

19:12

First, look at this.

19:14

A cross-shaped screw.

19:19

If you use a screwdriver of the wrong size...

19:25

as you can see, it strips the screw, and a screwdriver won't be able to turn it.

19:35

In come the pliers developed by Takasaki.

19:39

They look like normal pliers at first, but...

19:44

Just grab the screw and turn.

19:53

Wow! The screw was easily removed.

19:59

Look closely, and you can see that the pliers firmly grip the head, allowing it to turn.

20:12

The secret is in the uniquely designed tip.

20:20

When gripping a screw head, normal pliers make this slanted shape.

20:28

But Takasaki's pliers line up in parallel, like this.

20:35

Compare them, and the difference is clear.

20:42

Plus, the tips have these vertical grooves, so they don't slip when turning.

20:51

Normal pliers have horizontal grooves.

20:54

With horizontal grooves,

20:56

the direction of rotation of the screw is aligned with the groove,

21:00

so the pliers slide.

21:02

With vertical grooves, there's enough friction to prevent slipping.

21:07

That's the purpose of these grooves.

21:12

The pliers went on sale in 2002.

21:16

In an industry where 10,000 units is considered a hit,

21:19

these have sold some 770,000 units.

21:26

They've been patented in and outside Japan,

21:28

and are now exported to places like China, the U.S., and Europe.

21:35

They're beloved worldwide.

21:42

But in 2008, after the tool was released,

21:45

the firm suddenly found itself in peril.

21:52

The financial crisis.

21:56

The construction industry, which the firm had relied on for sales, was in dire straits,

22:01

throwing the firm into the red for the first time.

22:09

To create a new product that would bring things back into the black,

22:12

Takasaki turned to feedback received from customers.

22:19

He read them all, diving into what his customers found important.

22:28

He discovered that many customers wanted to be able to remove truss head screws.

22:36

Truss head screws are used in things like furniture and exteriors,

22:40

on things where a normal head would be bad.

22:43

That makes them hard to grab.

22:45

People had a big need to remove these hard-to-grab truss head screws.

22:51

Out of that emerged this new product.

22:56

At first glance, they look the same as the previous pliers.

23:02

With these, you can grab and remove truss head screws.

23:12

The secret is the shape of the tip.

23:15

The corners of the first version have been removed.

23:21

As a result, the tip adheres well to low heads, allowing them to be gripped.

23:30

The new pliers were a hit,

23:32

selling over 100,000 units a year and helping save the firm.

23:40

But thereafter, a new demand started to build.

23:46

Dealing with screws whose heads don't pop out at all.

23:52

Customers wondered if there was a way to remove such screws.

23:58

Screws whose heads don't emerge at all

24:00

are called "flathead" or simply "flat screws."

24:05

Once you screw them in they're totally flat against the surface.

24:10

Here's a flat screw that's been stripped.

24:13

When it's like this, of course, the pliers can't grip it.

24:18

Not at all.

24:22

How to unscrew screws that can't be gripped.

24:25

Takasaki pondered the problem for days.

24:31

He set his eyes on the furthest points of the stripped portion,

24:35

where four small corners remain.

24:44

He then developed this tool. Look closely at the tip.

24:52

Compared to a normal screwdriver, the cross-shaped tip is thicker.

25:00

Try this on a stripped screw head, and...

25:05

It grips the remaining four points so it can be unscrewed.

25:13

The specially designed tip grips the faint corners, and the screw can be removed.

25:24

Takasaki has developed over 30 screw removal tools.

25:28

His dream is to solve every screw problem imaginable.

25:37

I want to help people facing problems with screws.

25:40

It may be a niche, but it's a global niche.

25:44

It's a universal need,

25:46

so there's a large worldwide market for this.

25:51

I definitely want to keep trying new things in this field.

26:00

Hold up! There's more.

26:01

Like these hex screws.

26:03

Sometimes the socket gets totally worn out, right?

26:07

The company developed this tool with a drill at the head.

26:10

It burrows into the socket, providing a tight grip for removing the screw.

26:15

They've come up with a special tool for each type of screw. It's amazing!

26:22

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

26:26

We'll leave you with what came next for the mosquito coils

26:28

from the first half of the show.

26:30

See you next time! And stay inventive.

26:49

(The mosquito coils were invented in Japan some 130 years ago.)

26:54

(Since then, companies have created other products to repel mosquitoes.)

27:02

(This type releases insecticide by heating a pad containing it.)

27:09

(This diffuser type works by vaporizing a liquid insecticide.)

27:22

(And one spray from this keeps mosquitoes away for 12 hours.)

27:28

(These products are helping to prevent the spread of mosquito-borne diseases.)

27:35

Mosquito coils were born in Japan, and Japan continues to lead the field.

27:40

There's still much work left in the battle with mosquitoes.