According to Diginfo:

Bridgestone has developed the Air-Free Concept, a tire technology that uses a thermoplastic resin as it’s support structure instead of air.

“Because there’s no air in these tires, there’s no worry about punctures. Also, there’s no need to check the pressure in them, so they’re easy to maintain, too.”
“A feature of these tires is, they have spokes with a special curve, arranged in an interlacing fashion. This enables them to flex effectively without twisting, and behave just like ordinary tires, without producing a horizontal force.”

The spoke material is a reusable thermoplastic resin, meaning that the tires can be easily recycled, making them environmentally friendly.

“In an electric cart, the load on each wheel is about 50 kg. We’ve checked that these tires can amply support three times that load.”
“Regarding specific applications, we’d like to start with small-scale uses, such as personal mobility, and gradually move up to standard vehicles.”

The spokes, with their special curve, have a functional beauty. So Bridgestone expects that these tires will be used with the spokes revealed.
“If something becomes caught in the spokes, it’ll make them get stuck, and unable to change their shape. So we need to check how to avoid that, but we hope we can find a good way.”