The harm of three-proof paint to human body

Conformal paint is a kind of paint, but compared with common paints such as latex paint, its usage is more special. We can see it in the line class, because using it can protect the line from the erosion of the harsh environment around it, and it has good tolerance not only to high temperatures, but also to low temperatures. Conformal coating can be used on furniture, so what harm does conformal coating have to the human body?

A. The core materials of the three-proof paint are:

Silicone resin, acrylic resin, polyurethane, synthetic rubber, synthetic resin, modified resin, fluorosilicone resin, etc. The presence of these materials in the three-proof paint system does not cause any harm to the human body, because these organic materials themselves exist in our lives all the time and are completely harmless to the human body.

B.Solvent:

Here we mainly talk about solvents. 80% of the conformal coatings used on circuit boards seen on the market contain organic solvents. Solvents are divided into: A, B, C, B, C, C, C, alcohol, hydrogen, ether, etc. [Toluene, ethyl acetate, acetone, butanone, butyl acetate, cyclohexane, n-hexane, methanol, hydrocarbons, ether]. You can search for the chemical properties of these solvents on Baidu Encyclopedia, and then based on the conformal coating you are currently using, you can get the level of harm to the human body.

The types of solvents contained in the three-conformal paint used are:

1. If the conformal paint contains solvents such as toluene and xylene, benzene is highly toxic and irritating to the eyes and upper respiratory tract. At high concentrations, it has an anesthetic effect on the central nervous system. Chemicals like this are highly harmful to the human body.

2. If the solvents contained in the three-proof paint are ketones and alkanes, they are moderately harmful. Inhaling high concentrations of this product in a short period of time may cause obvious irritation symptoms to the eyes and upper respiratory tract, conjunctival and pharyngeal congestion, dizziness, headache, nausea, chest tightness, limb weakness, confusion, and staggering gait. In severe cases, there may be agitation, convulsions or coma. Some have hysterical attacks.

3. If the three-proof paint contains solvents, lipids, alcohols and other low-toxic hazards are used, but they also have chronic effects: long-term contact can cause neurasthenia syndrome, women may cause menstrual abnormalities, and skin contact often causes dry skin, chapped skin, and dermatitis.

4. If the conformal paint contains solvents such as hydrogen or ether, the harm will be minimal. Of course, even the most environmentally friendly solvents can be harmful if accidentally ingested. [Drinking too much liquor can also cause poisoning]

Conformal coating is an irreplaceable auxiliary material in the field of industrial manufacturing. We must use conformal coating in product design. In order to better protect the operator from harm, the harm of conformal coating to the human body should be minimized. We must normally prevent the harm of conformal coating during operation and pay attention to the following matters:

A. Personal protection of three-proof paint during the gluing process can be done by wearing gas masks, special tools, special gloves, etc. The gluing workshop must have good exhaust facilities.

B. During the gluing process, the coating operation should be carried out at a temperature not lower than 16°C [relative humidity not lower than 75%] to avoid air convection.

C. As a composite material, the circuit board will absorb moisture. If the moisture is not removed before applying the glue, the three-proof paint cannot fully play its protective role, and it may also cause the colloid to not dry. Pre-drying and vacuum drying of the PCB circuit board can remove most of the moisture.

D. When applying conformal coating on the circuit board, generally, chips, plug-ins, connectors, software sockets, switches, heat sinks, thermal conductive areas, plug-in areas, etc. are not allowed to be coated with conformal coating materials. It is recommended to use solder mask CS5001 for covering.

E. If you want to get a thicker coating on the PCB, it is best to apply 2-3 layers of thinner conformal coating, and the 2nd-3rd layers can only be applied after the first layer is fully cured.

F. The thickness of the circuit board paint film depends on the application method. The larger the amount of diluent added, the lower the glue viscosity and the thinner the glue coating thickness; the more solvent is added, the more volatile it is for the entire space, so the amount of solvent should be controlled.