Japan Black

Japan Black is the name of a lacquer or varnish used for metal, particularly iron. Because of its high bitumen content the coating provided a protective finish that was relatively durable and dried quickly. These features allowed for the extensive use in the production of automobiles in the early 20th century in the United States. It is also called Brunswick black and Japan lacquer.

Japan Black consisted mostly of asphaltic base dissolved in naphtha or turpentine, sometimes with other varnish ingredients. It is applied directly to metal parts, and then baked at about 200 °C (400 °F) for up to an hour. [http://www.americansolventscouncil.org/resources/dictionaryCoatingsGL.asp] Japan Black's popularity was due in part to its durability as an automotive finish. However it was the ability of Japan Black to dry quickly that made it a favorite of early mass produced automobiles such as Henry Ford’s Model T. Ford’s reliance on Japan Black led to the quip that the Model T was "“available in any color, so long as it was black.”"

Ford used two formulations of Japan Black, F-101 and F-102 (renamed to M-101 and M-102 after March 15 1922). F-101, the "First Coat Black Elastic Japan", was used as the basic coat applied directly to the metal, while F-102, "Finish Coat Elastic Black Japan", was applied over the first layer. Their compositions were similar: 25-35% asphalt and 10% linseed oil with lead and iron based dryers, dissolved in 55% thinners (mineral spirits, turpentine substitute or naphtha). The F-101 also had 1-3% of carbon black added as a pigment. The asphalt used in the Ford formulations was specified to be Gilsonite; it is cheap, acts as a curing agent for the oil, yields glossy dark surface, and increases the plasticity of the paint layer, making it less prone to cracking and peeling when subjected to vibrations and deformation. [http://www.mtfca.com/encyclo/P-R.htm]

While other colors were available for automotive finishes, early colored variants of automotive lacquers could take up to 14 days to cure, whereas Japan Black would cure in 48 hours or less. Thus variously colored pre-1925 car bodies were usually consigned to special orders, or custom bodied luxury automobiles.

The development of quick drying nitrocellulose lacquers (pyroxylins) which could be colored to suit the needs of the buying public in the 1920s lead to the disuse of Japan Black by the end of the 1920s. In 1924, General Motors introduced "True Blue" Duco (a product of DuPont) nitrocellulose lacquer on its 1925 model Oakland automobile marque products.

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