An early colour photography process using two glass plates: a colour screen plate, with red, green and blue filters, and a standard black-and-white negative plate.

(inorganic chemistry) A method for the production of metallic sodium by the electrolysis of molten sodium hydroxide

kraft process

(chemistry) A chemical process for the conversion of wood into wood pulp (for paper manufacture)

(inorganic chemistry) A method of extracting sulfur from underground deposits by pumping in superheated water.

(inorganic chemistry) The industrial process for the manufacture of sulfuric acid from sulfur and oxygen

plural of process butter

(chiefly historical) Renovated butter.

plural of processed cheese

The first commercially successful method of manufacturing synthetic gemstones, involving the melting of a finely powdered substance using an oxyhydrogen flame and crystallising the melted droplets into a boule.