Is the filling foam of the Jinda security door foamy?

There are generally four kinds of fillers for civil security doors: honeycomb paper, aluminum foil paper, and rock wool.

Foaming. Let's not talk about honeycomb paper.

1.The advantage of aluminum foil is that it can withstand high temperatures of up to 2,000 degrees Celsius.

But the disadvantages are also obvious, the metal filling conducts sound and temperature very quickly, and sound insulation and warmth are problems.

2.Rock wool is a kind of fireproof asbestos, which is much better than aluminum foil and sound insulation, but the fly in the ointment is that it irritates the skin and the respiratory tract.

There are also injuries, which can cause rock wool to overflow when some incorrect operations, resulting in skin contact or accidental inhalation.

3.Foaming is relatively not so much to take into account, if the aluminum foil paper conducts the sound quickly, the rock wool is to absorb part of the sound to reduce the sound, and the foaming is to rebound part of the sound to reduce the sound penetration, this can be reflected from knocking on the door, the sound of filling rock wool will be stuffy, and it is stuffy inside and out. Foaming is loud and brittle when listened to on the outside, and much weaker when listened to inside.

And foam insulation, which is already known as a thermal material, does not need to be repeated.

The above is the premise of real filling, and the local filling is not within the above range