Old Copy Machine With Purple Ink

Ditto machines made the purple copies that faded over time faster with exposure to light.

Old copy machine with purple ink.

Ideally each ink color would have its own screen. I guess we changed those. When i was in grade school i remember this copier that printed in purple ink and the secretary had to turn a handle to produce copies. The tray was only 1 4 deep.

The master for the ditto was only good for a limited number of copies as the solvent spirit dissolved. Both pieces of paper are stained with purple ink because they went through a machine invented in 1923 called a ditto machine or spirit duplicator. Ditto machine purple print and that smell. They have now been replaced by digital duplicators scanners laser printers and photocopiers but for many years they were the primary means of reproducing documents for limited run distribution the duplicator was pioneered by thomas edison and david gestetner with gestetner dominating the market up until.

There were two cylinders with a silkscreen belt running on them. The duplicator that produces purple copies is not a mimeograph. Duplicating machines were the predecessors of modern document reproduction technology. The stencil duplicator or mimeograph machine often abbreviated to mimeo is a low cost duplicating machine that works by forcing ink through a stencil onto paper.

It didn t use a drum. Mimeographs along with spirit duplicators and hectographs were a common technology in printing small quantities as in office work classroom. The mimeograph process should not be confused with the spirit duplicator process. Who could forget the purple ink that rubbed off on your hands the copies had a smell that was recognised by any 1960 70 s school kid.

A ditto machine was a primitive photocopier that used a solvent like methylated spirits or ammonia to transfer ink from the master copy the template if you will onto other pieces of paper. The stencil was thin rubber backed with paper and it was critical to get this on right while peeling the paper backing. Sold a hectograph kit as late as 1974 tray gelatin a few sheets of purple inked paper and that thick cover. We just cleaned it out to change color.

Stencil duplication was a low cost printing method that worked by forcing ink through waxed paper stencils on to target paper.