Celluloid dissolves in acetone, sulphuric ether, alcohol, oil of turpentine, benzine, amyl acetate, etc., alone, or in various combinations of these agents. The following are some proportions for solutions of celluloid:

I

Celluloid.........     5 parts

Amyl acetate......   10 parts

Acetone...........   16 parts

Sulphuric ether ....   16 parts

II

Celluloid.......... 10 parts

Sulphuric ether .... 30 parts

Acetone........... 30 parts

Amyl acetate...... 30 parts

Camphor......... 3 parts

III

Celluloid.......... 5 parts

Alcohol........... 50 parts

Camphor......... 5 parts

IV

Celluloid.......... 5 parts

Amyl acetate...... 50 parts

V

Celluloid.......... 5 parts

Amyl acetate...... 25 parts

Acetone........... 25 parts

Softening and Cementing Celluloid

If celluloid is to be warmed only sufficiently to be able to bend it, a bath in boiling water will answer. In steam at 120° C. (248° F.), however, it becomes so soft that it may be easily kneaded like dough, so that one may even imbed in it metal, wood, or any similar material. If it be intended to soften it to solubility, the celluloid must then be scraped fine and macerated in 90 per cent alcohol, whereupon it takes on the character of cement and may be used to join broken pieces of celluloid together. Solutions of celluloid may be prepared: 1. With 5 parts, by weight, of celluloid in 16 parts, by weight, each of amyl acetate, acetone, and sulphuric ether. 2. With 10 parts, by weight, of celluloid in 30 parts, by weight, each of sulphuric ether, acetone, amyl acetate, and 4 parts, by weight, camphor. 3. With 5 parts, by weight, celluloid in 50 parts, by weight, alcohol and 5 parts, by weight, camphor. 4. With 5 parts, by weight, celluloid in 50 parts, by weight, amyl acetate. 5. With 5 parts, by weight, celluloid in 25 parts, by weight, amyl acetate and 25 parts, by weight, acetone.

It is often desirable to soften celluloid so that it will not break when hammered. Dipping it in water warmed to 40° C. (104° F.) will suffice for this.