Applied color label
The term Applied Color Label (ACL; also: Pyro) means the (direct) label printing on a glass bottle.
Beginnings
The printing process for several bottles took hours, as ten minutes of drying time were necessary for each color, as pine oil was used as a carrier for the color pigments in the beginning . Each additional color then required this time, so that the first ACL bottles rarely had a multi-colored print.
Further development
At the beginning of the 1950s, a total capacity of 50 to 70 bottles per minute was achieved, but since pine oil was still used, the drying times could not be shortened significantly. Through the use of thermal waxes as a pigment carrier, the output was increased to 120 to 130 bottles in the mid-1950s and the application process was fundamentally improved with this new carrier. The colored wax was pressed through a thin, highly heated metal mesh. The contact of the hot wax with the cooler glass surface led to an immediate drying of the paint and the bottle could be transported to the next paint application. At the end of the entire ACL process, there was the cooling furnace. This had two tasks: to fix the color on the bottle and to take the tension out of the glass, which had arisen from the high temperatures of the last paint application (590 ° C to 650 ° C). The label applied in color in this way quickly found acceptance among bottle manufacturers, as it combined the colors of a paper label and the durability of an embossing.