| 摘要 |
<p>The instant invention concerns a new process for the manufacture of holders containing photographs, for tombs or tombstones, made up of an opaque support and a transparent plexiglass cover, made at the same time by a compressed air moulding process, which starts with two plexiglass sheets, positioned one on top of the other and clamped within a special form, where a matrix punch exerts pressure on the two sheets, and after being brought to a softening temperature, compressed air is blown onto them so that they are moulded at the same time by contact with the external wall of the punch.</p> |
