Blueprint paper

In 1924 the German company Kalle Co. in Wiesbaden began production of blueprint paper, i.e. a diazo reprographic paper. In that process a sheet coated with a diazonium compound was exposed to an optical image and developed by diazo coupling using a mono-... 

Cyanide ion, CN , reacts with Fe " to form the blue dye that is used in blueprint paper. Hydrocyanic acid, HCN(aq), is a weak acid, with... 

A less frequently employed example of a chemical effect would be that of escaping ammonia when it makes contact with ozalid paper (blueprint paper) or with other materials suitably prepared and wrapped around the outside of the specimen. Leaks are then detected based on the discoloration of the paper. 

Ammonium Iron(IIT) Oxalate. This mixed salt is produced as an emerald-green crystalline tnhydrate. The compound is not stable lo light. It was once used extensively in the manufacture of blueprinting papers. 

Follow this procedure Add 3 tablespoonfuls of ferric oxalate to 3 cups of water in one of the shallow pans. Dip the sheets of white paper, a few at a time, into the ferric oxalate solution and allow it to dry in a dark place. Ferric oxalate is the chemical for treating the white paper and turning it into blueprint paper. If you are not going to use the blueprint paper immediately, store it in the black envelope when it is dry. 

With the drawing ink, make some line drawings on the tracing paper. Attach them to sheets of your blueprint paper with paper clips. Place the opaque... 

At the end of the time of exposure, remove everything from the blueprint papers. Dip the blueprint papers, one after the other, into the developing solution. It will only take a few seconds for the blue color to appear. When it does, remove the papers and carefully wash away the film of chemical from the white areas with a cloth moistened with water. Let your blueprints dry and flatten them under a heavy book before you put them away for good. 

Results The ferric oxalate solution was colorless. When it coated the white paper, the white paper didn t change color. Nevertheless, the white paper became blueprint paper simply because it was coated with ferric oxalate. ... 

The sunlight didn t affect the color of the blueprint paper either, but it did produce a chemical change that you could not see. The equation for the reaction induced by the sunlight is ... 

When you put the exposed blueprint papers into the developing solution, there was a reaction between the ferrous oxalate and the potassium ferricyanide. This reaction caused the blue color to appear. 

Where the blueprint paper remained white, this reaction did not take place, because the drawing ink, the opaque objects and the dark areas of the photographic negatives had prevented exposure of those areas to sunlight. If you had left the ferrous oxalate on the blueprint, it would have eventually reacted with sunlight and ruined the blueprint. Washing the ferrous oxalate away, therefore, made the blueprint permanent. 

Blueprints are based on a photochemical reaction. The paper is treated with a solution of iron(III) ammonium citrate and potassium hexacyanoferrate(III) and dried in the dark. When a tracing-paper drawing is placed on the blueprint paper and exposed to light, Fe ions are reduced to Fe ions, which react with hexa-cyanoferrate(III) ions in the moist paper to form the blue color on the paper. The lines of the drawing block the light and prevent the reduction of Fe ions, resulting in white lines. Find out how sepia prints are made, and report on this information. 

Use Tempering steel, etching liquid, production of pigments, electroplating, sensitive coatings on blueprint paper, fertilizer compositions, laboratory reagent. 

Use Manufacture of sodium ferricyanide, blue pigments, blueprint paper, anticaking agent for salt, ore flotation, pickling metals, polymerization catalyst, photographic fixing agent. 

Use Mordant in dyeing, ceramics, glass, source of tin for electroplating and immersion plating, textile fireproofing, stabilizer for hydrogen peroxide, blueprint paper, laboratory reagent. 

The roots of DNQ-novolac resists stretches all the way back to the ozalid process, mentioned above, which dates to the invention around 1917 of the process for making architectural blueprint papers by Gustav Kogel (1882-1945) and... 

Prodncts and Uses Applications include gummed tape, cartons, blueprint paper, and printing plates. A ton of skins yields about 50 gallons of liquid glue and adhesive. 

Hazardous Decomp. Prods. Heated to decomp., emits acrid smoke and irritating fumes Uses Blueprint paper nutrient supplement may be used in infant formulas Regulatory FDA 21CFR 184.1298, GRAS Japan approved... 

Sodium ferrocyanide blueprint developer Urea peroxide blueprint paper... 

Blueprint paper Dye mordants Ceramics and glass Tin electroplating Textila flrepromittg StabiUzsrfor hydrogen peroxide... 

Ozalid Reproduction Products Division, General Aniline and Ffim Corp., 140 West 51 st St., New York, N. Y., USA (Blueprint paper). 

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