Читать книгу Henley's Formulas, Recipes and Processes (Applied Chemistry) - Various - Страница 6

1.
Copper sulphate	1 part
Potassium chlorate	1 part
Water	8 parts
Boil until salts are dissolved.
2.
Aniline hydrochlorate	3 parts
Water	20 parts
Or, if more readily procurable:
Aniline	6 parts
Hydrochloric acid	9 parts
Water	50 parts

By the use of a brush two coats of solution No. 1 are applied while hot; the second coat as soon as the first is dry. Then two coats of solution No. 2, and the wood allowed to dry thoroughly. Later, a coat of raw linseed oil is to be applied, using a cloth instead of a brush, in order to get a thinner coat of the oil.

A writer in the Journal of Applied Microscopy states that he has used this method upon some old laboratory tables which had been finished in the usual way, the wood having been filled oiled, and varnished. After scraping off the varnish down to the wood, the solutions were applied, and the result was very satisfactory.

After some experimentations the formula was modified without materially affecting the cost, and apparently increasing the resistance of the wood to the action of strong acids and alkalies. The modified formula follows:

1.
Iron sulphate	4 parts
Copper sulphate	4 parts
Potassium permanganate	8 parts
Water, q. s.	100 parts
2.
Aniline	12 parts
Hydrochloric acid	18 parts
Water, q. s.	100 parts
Or:
Aniline hydrochlorate	15 parts
Water, q. s.	100 parts

Solution No. 2 has not been changed, except to arrange the parts per hundred.

The method of application is the same, except that after solution No. 1 has dried the excess of the solution which has dried upon the surface of the wood is thoroughly rubbed off before the application of solution No. 2. The black color does not appear at once, but usually requires a few hours before becoming ebony black. The linseed oil may be diluted with turpentine without disadvantage, and after a few applications the surface will take on a dull and not displeasing polish. The table tops are easily cleaned by washing with water or suds after a course of work is completed, and the application of another coat of oil puts them in excellent order for another course of work. Strong acids or alkalies when spilled, if soon wiped off, have scarcely a perceptible effect.

A slate or tile top is expensive not only in its original cost, but also as a destroyer of glassware. Wood tops when painted, oiled, or paraffined have objectionable features, the latter especially in warm weather. Old table tops, after the paint or oil is scraped off down to the wood, take the above finish nearly as well as the new wood.