Bitumen of Judea

In Ancient Egypt mummies were wrapped in cloth dipped in a solution of bitumen in oil of lavender which was known variously as Syrian Asphalt or Bitumen of Judea. On exposure to light the product hardened and became insoluble. It would appear that this process involved the action of chemical cross-linking, which in modem times became of great importance in the vulcanisation of rubber and the production of thermosetting plastics. It was also the study of this process that led Niepce to produce the first permanent photograph and to the development of lithography (see Chapter 14). 

PHOTOGRAPHY/ PHOTOLITHOGRAPHY ON GLASS, ZINC, PEWTER SUBSTRATES 1 (1826) BITUMEN OF JUDEA (1839) AMMONIUM DICHROMATE ON PAPER (1936) PRINTED CIRCUH BOARD... 

The role of bitumen of Judea in the invention of photohthography and photography is described in Chapter 2, for it was the resist that was used to the capture the first permanent image from nature. 

It must be mentioned that the exposure requirements of dichromated gelatin are orders of magnitude less than those of bitumen of Judea resist material. In 1855, A.L. Poitevin demonstrated photolithography on stone sensitized with dichromated gelatin, glue, albumen, and gum. ... 

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