Moisture is usually normal and weak on the board. The amount of water that increases the efficiency of tolerance among leaders, increases the speed of movement, increases the Q number, and connects the steering wheel. Often you look at the frames of the floorboard that will work with metal screws and brands and steam type like oxygen, and the harmful effects. Demonstrate a multi-purpose approach to wireless programs and the potential for reducing or declining the potential of telecommunications technology as a result of the business system.

efficiency of tolerance


The acrylic Conformal Coating is flexible and provides comprehensive protection. Because it is a one-component system, it has good adhesion, simple operation, low requirements on equipment and conditions, convenient construction, high transparency, high brightness, short operating cycle, etc., so they are easy to use and easy to remove. Some acrylic products meet military standards, they dry quickly and do not dry, and can be removed with a matching organic solvent, so this type of circuit board Conformal Coating is one of the most versatile and most effective products on the market.

Whether the Conformal Coating is toxic depends on the type of Conformal Coating thinner and solvent used. If the Conformal Coating uses toluene and xylene as thinner, this chemical is harmful to the human body. If it is used, it is harmful to lipids and alcohols. small. Xylene is moderately toxic and has a stimulating effect on the eye and upper respiratory tract. At high concentrations, it has an anesthetic effect on the central nervous system. Although there are many environmentally-friendly Conformal Coating on the market, in actual use, we still need to take protective measures and wear gas masks when using them.

There Are Four Types of Conformal Coating Use Processes:

1. Brushing - the use of universal, can produce an excellent coating effect on a smooth surface.

2. Spraying - the use of spray can type products can be easily applied to maintenance and small-scale production use, the spray gun is suitable for large-scale production, but these two spray methods require higher accuracy of operation, and may produce Shadow (the place where the lower part of the component is not covered with three anti-paint).

3. Automatic dip coating - dip coating to ensure complete filming, and will not cause material waste caused by over-spraying.

4. Selective coating of the film - accurate coating and no waste of material, suitable for large-volume coating, but high requirements for coating equipment. Most suitable for large-volume coatings. Use a set XYZ program to reduce cloaking. When the circuit board is painted, there are many connectors that do not need to be painted. The adhesive tape is too slow and there is too much residual glue when tearing. Considering the shape, size and position of the connector, a combined cover can be used to position it with the mounting hole. Cover the parts that are not painted.

coating of the film


Operation Process Requirements

1. Clean and bake the board to remove moisture and moisture. The dust, moisture and oil on the surface of the object to be coated must be removed first so that it can fully exert its protective effect. Thorough cleaning ensures that corrosive residues are completely removed and the Conformal Coating adhere well to the surface of the board. Drying conditions: 60 ° C, 10-20 minutes, after removing in the oven, the hot coating effect is better;

2. Apply by brushing method, the brushing area should be larger than the area occupied by the device to ensure that all the devices and pads are covered;

3. When the brush is applied as flat as possible, there should be no dew after brushing, the brush should be flat, and there should be no exposed parts, preferably between 0.1-0.3mm.

4. Before brushing and spraying, ensure that the diluted product is thoroughly stirred and allowed to stand for 2 hours before brushing or spraying. Use a high quality natural fiber brush and gently apply a dip coating at room temperature. If using machinery, the viscosity of the coating should be measured (using a viscosity agent or flow cup) and the viscosity can be adjusted with a diluent.

5. The board assembly should be immersed vertically into the paint slag. Do not immerse the connector, unless carefully covered, the board should be immersed for 1 minute until the bubble disappears, then slowly take out. A uniform film layer is formed on the surface of the board. Most of the paint residue should flow back from the board to the dipper. TFCF has different coating requirements. The board or component should not be immersed too fast to avoid excessive air bubbles.

6. When using again after dip coating, if there is skin on the surface, remove the epidermis and continue to use.

7. After brushing, lay it on the bracket and prepare to cure. It is necessary to use heating to accelerate the curing of the coating. If the surface of the coating is uneven or contains air bubbles, it should be allowed to stand at room temperature for more time to solidify in a high temperature furnace to allow the solvent to flash out.

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