In the museum exhibition hall, we can see not only the large cabinets arranged along the walls, but also the central cabinets that are often placed separately in the middle of the exhibition hall. What they have in common, that is, facing the audience, is separated by glass. But there are also exhibitions, where the exhibits are often oil paintings and sculptures, which are not placed in the display case, but use safety lines and fences to control the distance between the audience and the exhibits.

It can be seen that the two methods of using glass display case and setting up fences have been established after the birth of modern museums, and have now become the tradition of museum exhibitions. Using glass display cabinets to isolate the exhibits from the general environment of the exhibition hall, on the one hand, it can avoid the audience's contact with the exhibits and avoid the risk of damage; on the other hand, it can create a small environment inside the exhibition cabinets, which can keep the exhibits in constant temperature and humidity. It is especially important for cultural relics of organic matter and metal.

What kind of display case glass is good?

There are two main evaluation indicators: display and safety.

Exhibiting property

As we all know, light passing through glass is bound to change. The so-called display is the nature of convergence between looking at the exhibits through the glass and looking at the exhibits directly. It can also be subdivided into two indicators: light transmittance and reflection.

The glass of the showcase with high light transmittance will lose less light through the glass, and the audience will feel that the glass is very clear. The glass of the showcase with high reflectivity is easy to reflect when the light enters the glass, and the audience can see the reflected figure from the glass, affecting the visual effect. Although the light transmittance of ultra-white glass is high, but the reflectivity is not ideal, it is still easy to form a figure. At present, several domestic glass manufacturers can produce low reflection glass with a reflectivity of less than 1%, and there is basically no figure in the visit, which basically solves the problem of reflectivity.

Security

The glass of the museum display case isolates the exhibits from the environment, so it must be firm. The so-called safety is the property of resisting force through glass without breaking. It can also be subdivided into two indicators: firmness and self-explosion prevention.

A hidden danger to the safety of the museum is that there are malicious robbers who directly smash the glass of the exhibition cabinets and take away the exhibits. At present, the vast majority of museums use tempered glass made of ordinary glass after rapid heating to high temperature and uniform cooling, and its resistance to violent impact and bending has been greatly improved compared with ordinary glass. at present, the glass of the exhibition cabinet can be basically unbroken, and its firmness is not the same as before.

But tempered glass has an unpredictable risk-self-explosion, with a self-explosion rate of about 1 ‰ to 3 ‰. Although it is not high, it has brought some losses to the museum.

The main factors affecting the self-explosion of tempered glass are as follows:

1. The greater the toughening stress, the easier it is to explode.

2. The self-explosion probability of glass is proportional to the cubic power of the radius size of impurity particles.

3. The closer the impurity is to the neutral layer of the glass, the easier it is to self-explode.

4. The greater the temperature change (or the uneven heating of the glass), the easier it is to explode.

5. The greater the force on the glass, the easier it is to self-explode, so the glass for the ceiling is more likely to explode than the vertical glass for the curtain wall.

6. For the same glass, the larger the volume, the greater the probability of self-explosion.

At present, the museum's strategy is to use glue to bond two layers of toughened glass together, which is called glue-filled glass, which can not only effectively reduce the phenomenon of self-explosion, but also the glass fragments after self-explosion are bonded and will not hurt the exhibits.

The above is the introduction of high-quality museum glass display cabinets. If you want to know more about glass display cabinets, please feel free to contact us.