The one-time molding (no border) technology is the invention patent of a painter from Inner Mongolia, which is called "Peng's calligraphy shaping method".
The general approach is to raise the height of the yin and yang molds to leave enough gaps. A high-elastic rubber "shaper" is placed between the male and female molds to protect the blister sheet from breaking when it is pressed and stretched.
This method can deeply embosse the characters, with the height of the characters reaching 5---8 cm. The space is enough to install LED and other light sources, so there is no need to surround the edges. This not only saves the cost and time of the edge strips, but also makes the finished product better sealed, dustproof and waterproof.