Welding mask

Fragment of a PCB where you can see the green coloration of the welding mask.

A welding mask is a coating layer that receives the printed circuit boards to protect areas of the copper layer where it is not desired to apply solder paste on SMD or THT technology. It prevents the occurrence of short circuits and protects copper from corrosion and other external agents. Usually includes a dye that gives it a green coloration; although it is also available in other colors like red or blue. It is of epoxy composition, of application by serigrafía. Application

The solder resist ink is used to print printed circuit boards, and to mask the areas where the alloy used for soldering electronic components is not to be used, is not recommended for other use or decorative ink. The printing system will vary according to the process to be subjected to the surface to be worked, in the case of circuits that are covered by a layer of metal by electrolytic deposition, Tin-Lead type the impression will be the negative of the image, leaving alone the welding lobes exposed and with open meshes of good discharge, as by subjecting these plates to the soldier by "wave" the refusion of the metal under the ink will cause it to "wrinkle."

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