| 摘要 |
<p>The printed circuit on a flexible base has a protective coating to prevent solder used in making connections from flowing across the circuit and producing unwanted short circuits. The coating is formed from a varnish which adheres to the base and remains flexible after polymerisation. In particular the varnish is of a photohardening type, including a polythiol and a polyene based on acetyl-vinyl such as that of reference Sm19 of the Thiokol Society. The varnish provides flexible protection for printed circuits and does not peel even after long periods of use.</p> |
