BKTWE: Illuminated capacitive buttons with interchangeable slide-​in strips

For devices, machines and sys­tems where the but­ton assign­ment takes place rel­a­tively late, it has been quite dif­fi­cult to indi­vid­u­al­ize the let­ter­ing on HMIs with a glass sur­face. This is due to the fact that glass print­ing is one of the first process steps and indi­vid­u­al­iz­ing the print­ing using screen print­ing does not appear to make eco­nomic sense. For this rea­son, we have trans­ferred a solu­tion from the world of HMIs with foil sur­faces to the glass era: the self-​printed, exchange­able slide-​in strip. In extreme cases, the but­tons can only be printed when the machine is put into oper­a­tion — using a stan­dard trans­par­ent film on a stan­dard laser printer. 

This is made pos­si­ble by the new car­bon nan­otube tech­nol­ogy. This allows trans­par­ent con­duc­tive lay­ers to be pro­duced using con­ven­tional screen print­ing and thus opti­mized to the exist­ing geom­e­try, even for small to medium quantities.