By hqt
Anti-static gloves are good to use to prevent electrostatic discharge when handling sensitive products such as electronic components and modules. Due to the sufficient electrical conductivity of the material of the gloves, the electrostatic charge does not accumulate and flows down to grounded surfaces.
Anti-static models for electronics must also be suitable for cleanroom environments, which mean that they do not leave lint or other small particles in use.
ESD patterns are available in nylon or polyester knitting or sewn in a similar fabric. Knitted models are preferable, as they provide a better fit to the hand and tactile sensitivity of the fingers. According to the surface resistance of the material, anti-static gloves conditionally divide into charge-dissipating (dissipative) and charge-conducting (conductive).
The first type characterizes by a surface resistance of the order of 10 9 - 10 10 Ohm, for the second - 10 5 - 10 6Ohm. As a rule, for dissipative models, a synthetic thread saturated with carbon fiber is good to use, while conductive models come by adding the thinnest copper wire to the synthetic thread. To reduce slip when working with small parts, the surface of the fingertips or the entire palm is easy to coat with a polyurethane compound.
There are also anti-static gloves for various industries with an increased level of protection against cuts, exposure to extreme temperatures and aggressive environments.
Due to friction and movement, everyone charges with static electricity. Electrostatic discharge occurs several times a day, but this is usually imperceptible to humans and has no consequences. The situation is different when it comes into contact with conductive objects.
Wearing ESD gloves helps to protect microelectronic components or elements. Thanks to the gloves, the charge is easy to discharge continuously with every contact with a grounded surface.
The abbreviation ESD stands for electrostatic discharge. A prerequisite for an electrostatic discharge is two objects with a different potential. The potential difference arises, for example, from static electricity (e.g. walking on a carpet).
Although the terms “ESD” and “antistatic “often appear in the same context. They are by no means synonymous unlike antistatic.
Electrostatic discharge is not a danger to humans, but rather harmful to sensitive electronic components. ESD protection is therefore good to use wherever damage to workpieces or devices is to prevent through controlled discharge of charge.
In contrast, antistatic protective equipment ensures (e.g. antistatic safety shoes) to protect employees from electrical charging or to ensure that the charge discharge. This is necessary, for example, if there is a risk of an electric shock from live parts or electrical devices.
Both ESD and anti-static gloves are about volume resistance. The EN 61340-5-1 standard for protection against electrostatic charging in connection with technical devices defines that the ESD area defined there represents a delimitation of the antistatic area.
However, antistatic safety shoes are not always ESD-capable, but only if their contact resistance is not above the ESD upper limit of 35 megaohms.
If both objects with different potentials come within a few millimeters of each other, an abrupt equipotential bonding occurs. There is a sudden and rapid transfer of charge from one object to another.
An electrostatic discharge can not only take place between objects. As mentioned above, humans also become statically charged through static electricity. If the humidity of the environment is below 20%, humans can charge up to 35,000 volts. At a humidity of 65%, a charge of less than 1,500 volts is possible.
Electrostatic discharge is only unpleasantly felt by humans from around 3,000 volts. Electronic components or assemblies severely affect by even the smallest charges. For example, 30 volts are enough to damage electronic components, 50 volts to create flammable sparks and 100 volts to erase information on magnetic storage media.
Components such as reading heads on hard disks or microchips are the most sensitive. 5 volts are enough to damage them during production.
In particular, the energy of a static discharge destroys the semiconductor structures inside a component. This weakens insulation distances and conductor tracks.
How anti-static gloves determine with the help of EMC measurements must be examined in an appropriate laboratory.
They usually only become apparent when the customer is using them. In addition to the resulting repair costs, it is not uncommon for the dealer to face anti-static gloves costs for replacement services and penalties. Likewise, goods that already damage upon delivery usually result in damage to the company's image.
However, the statistics of a semiconductor manufacturer show that in practice ESD damage occurs as a cause in approx. 25% of the components returned as defective.
To prevent ESD damage, anyone involved in the manufacture or maintenance of sensitive electronic components or assemblies should protect themselves against unwanted electrostatic discharge. This applies to the entire manufacturing process.
Anti-static gloves are particularly important in these areas:
Hazards associated with electrostatic discharge also arise when handling flammable gases and liquids, such as at gas stations or gas plants. In addition, ESD can cause dust explosions from dust-dry bulk goods such as coal, flour or grain.
In order to protect electronic components, it makes sense to wear ESD gloves, among other things. Each time they come into contact with a grounded object. They continually lose charge.
Thanks to liners, in which conductive special fibers (e.g. made of carbon or copper) incorporate. This conductivity of the anti-static gloves achieves. Some homogeneous materials, such as nitrile, can also have antistatic properties.
In the case of protective gloves with an additional coating, the gloves can only be made antistatic if the coating also mixes with conductive particles (such as silver ions).
