Questions after use of the showerhead;

When the shower is stopped, water comes out from air inlet, is it broken?

It is not broken. To prevent the growth of bacteria left inside of showerhead, it was designed to drain them from air inlet automatically that is why it seemingly drips some water out after use.

How do I check the generation of microbubbles?

The bubbles can be seen under the water, but the color does not turn to be milky color.
When it comes to check it with a bathtub, turn off the light and put a spotlight in the area of spout, then you can see the bubbles easily.
Or a faint sound can be heard from an air inlet.

After setting the showerhead and use it, but I feel like not generate the microbubbles from showerhead. Why is it happen?

Because of the water amount and water pressure may not be enough condition to generate microbubbles.

When I turn the shower on or during using the showerhead, the water comes out from an air inlet, is it broken?

If the status that water come out from an air inlet during using the showerhead, microbubbles has not been generated.
This could be caused by filter’s clogged and calcium stain on a plate. Please refer to the user’s manual below.

- Purebble II(PDF:671KB)
Purebble II / User’s manual - Purabble Pro, Baby, Petit(PDF:1.09MB)
Purabble Pro, Baby, Petit / User’s manual

Questions about microbubbles;

Does transparent water turn to be milky color when microbubbles has been generated in the water?

Microbubble does not always seem milky when microbubbles exist in the water.
At least required condition of becoming milky color can be seen is the followings.
・Bubble size must be a few ten micron to a few hundred microns
・Number of bubbles must exist around 500,000bubbles/cc(50millions/L) or above
So the condition of bubbles size and number of bubbles changes far from this condition eventhough microbubbles existed.
We have four types of patent for microbubbles that generated such as "Ejector method", "Cavitation method", "Spiral flow system" and "Pressurizing dissolving method". Only "Pressurizing dissolving method" can be kept stably milky color condition when microbubbles exists in the water.

There showerhead have different types , like the air intake type and non-take in the air type. What is the difference between them?

A type of air intake called “Ejector method” means that the air exist outside to be taken spontaneously into the showerhead nozzle and generate the microbubbles. This can be stably generate the bubbles with required water pressure.
Non-take in the air type must clear several requirement to generate the microbubbles. It called "cavitation type", the method that making existed air in the water turn to be the bubbles, so bubbles generating system is different.

Which one is more effective, "microbubbles" or "nanobubbles"?

Nanobubbles sounds nicer as it is much smaller bubbles, however, not a matter of its size related to all effects. We have been researched and developed microbubbles and nanobubbles for more than 20 years, we verify that there are most suitable bubble size for different purpose of use.
Nanobubbles are very tiny as smaller than micro size and its effect of floating and washing away of extremely tiny dust nearly invisible to human eye sight, which suite for washing something like precision equipment.
For microbubbles are suite to wash away the stain of tableware, skin's exceeded sebum.

"Micro-nano-bubbles showerhead" is introduced in the market recently, is it possible to generate nanobubbles with showerhead?

We measured a called “micro-nano-bubbles showerhead” in our labolatory whether nanobubbles are generated or not, however, we could not validate generated nanobubbles. It is not possible to generate nanobubbles with supplying water pressure in household in Japan.

Since we are the manufacture, not only we sell the showerhead but also we produce some products which generate Micro-nano-bubbles and nanobubbles for research and industrial use. In this generating method called "pressure dissolution method" and in order to measure the bubble size, we use the measurement equipment of nano particles.