There are many selection criteria for printed circuit board pastes. What are the selection criteria for printed circuit board pastes?
I often encounter some friends who make circuit boards: printed circuit board paste has many technical indicators, wire width, line spacing, etc., how to choose the paste when choosing the paste? According to the line width, line spacing, whether it is sinking gold , Environmental protection, process, etc. In fact, the choice of ink paste is not related to line width, line spacing, surface treatment
There is a relationship, it depends on the customer’s needs. If the customer wants to make green oil, red oil, white oil, black oil, blue oil, butter, there is actually no problem, but the price of green oil and other inks are slightly different . And some boards will have special requirements, choose conductive paste, such as: carbon paste, silver paste, copper paste, high resistance ink, etc., the conductive performance is relatively strict.
For example, the LED lamp board needs to use white oil on the aluminum substrate, and green oil and black oil are rarely used. However, if the white oil is used, the characters cannot be white, and red, black, and yellow must be used. Only then can the characters be clearly seen. In addition, the circuit board on the mobile phone has high requirements, there are various types, and the line width and distance are also relatively
There are many types of precision, and there are many kinds of holes. Mobile phone boards can only be made by manufacturers that make precision circuit boards. It is difficult for ordinary manufacturers to produce. The process requirements are actually not much different from ordinary boards. Green oil or blue oil is used, and the surface treatment is heavy. Gold and BGA do anti-oxidation, the normal thickness is (this is the most common), and more common.
The selection criteria for printed circuit board pastes can be listed as follows:
1. Color–Solder resist ink has many colors, such as green, blue, yellow, orange, red, black, white, silver gray, brown and so on.
2. Viscosity: The viscosity of photosensitive solder resist ink is generally around 280PS, while UV curing solder resist ink
The viscosity is generally around 200PS, the viscosity of the photosensitive circuit ink is generally around 80PS, the viscosity of the metal anti-etching ink is generally around 120PS, and the viscosity of the inner circuit ink is generally around 10PS. Then we can look at the fineness of the ink, this parameter we can generally use a scraper fineness tester to test
, That is, apply some ink to the fineness meter, and then scrape down with a doctor blade. During this process, the ink will become lighter and lighter. At this time, you can roughly distinguish a less clear critical line, then The scale corresponding to this critical line is the fineness of this ink.
3. The hardness of the printed circuit board paste, which we have roughly talked about before, you can use a pencil hardness tester to test how hard the cured ink is. In the pencil hardness tester, we often use The pencils are divided into 1H, 2H, 3H, 4H, 5H and 6H. In addition to the above parameters, when choosing the paste, you can also ask the supplier about the adhesion of the ink and how long the storage period is, and if the LED aluminum substrate white oil If you want, you can also ask what the reflectivity of the ink is, how white the whiteness is, or what kind of white, whether it is milky white or pure white, whether it has a blue phase or a red phase, and so on.
All in all, the standard of printed circuit board paste is not the same, only the ink suitable for your product is the best ink. Our company has been deeply involved in the paste field for several years, including conductive copper paste, conductive silver paste, silver copper paste, etc. Customers provide comprehensive solutions.