Views: 79 Author: Site Editor Publish Time: 2017-12-12 Origin: Site
Conductive Printing, also known as conductive ink pad printing, conductive paint screen printing, printing conductive paste ink, which is composed of printing conductive materials, like gold powder, silver powder & carbon powder, and dispersed in the bonding material. Conductive Printing ink has a certain degree of conductive properties, can be used as silicone rubber keypads' conduction paint material. The bigger the printing ink area & thickness the conductive keypad is, the less resistance it will be.
Conductive Printing Classification
Conductive paint screen printing with gold powder is stable and conduction property is better than other material, however, the price is expensive and the application is limited to thick film integrated circuit.
Conductive ink pad printing with silver powder is widely used in membrane switches. When printing ink is not dry enough, resistance will increase, so after conductive paint, the best way is to put it into ultraultrared drier for drying under the working temperature 120 ~ 130 ℃.
Conductive Printing ink with copper powder is cheaper than the silver one, meanwhile it is oxidizable.
Printing Conductive Paste Ink with carbon powder is widely used as silicone rubber keypad & membrane switches’ conductive method.
Conductive Printing Application
Conductive ink is printed on the conductive substrates, to make it have the ability of conduction current and eliminating accumulation of electrostatic charge. Conductive printing ink, usually printed on the conductive substrates, like silicone, rubber, plastic, glass, ceramic or cardboard etc. There are many printing methods, such as screen printing & transferring printing, letterpress printing, flexographic printing, gravure printing and pad printing.
Other Conduction Methods
Silicone Rubber Keypad & Keyboard have many other conduction methods, such as carbon pills & graphite pads, metal domes, nickles pills, copper & golden pills.
Carbon Pills is a very common method of silicone conductive keypad with the advantage of lower resistance, stable property, long lifespan and cost-economic.
Silicone keyboard with Golden Pills & Copper Pills is mainly used in Automobile Products. Although Golden Pills have the lowest resistance, while it is expensive and the production efficiency is low.
Rubber keypad with Nickel Pills is mainly used in automobile, medical equipment, military and aerospace products. The production process is the same with the black carbon pills, and production efficiency is higher than the golden pills, while the price is expensive.
From the above, conductive printing is highly recommended with the advantages as followed:
1. Rubber keypad with Conductive Printing ink have no limitation of conductive substrates area's shape, it can be round, square, triangle, or any other shape.
2. Conductive Ink Printing Keypad can be reworked.
3. Conductive Keypad via conductive paint screen printing is the most cost economic then metal domes, golden pills & nickle pills.