A film splicer is a device which can be used to physically join together lengths of photographic film

Photographic film

Photographic film is a sheet of plastic coated with an emulsion containing light-sensitive silver halide salts with variable crystal sizes that determine the sensitivity, contrast and resolution of the film...

. It is mostly used in motion pictures. The units are made in various types depending on the usage.

Cement splicers

Cement splicers join films together by using a chemical called film cement which is made of film base dissolved in a solvent. The emulsion is removed from the area to be joined and the base of the other end is brought into contact with it.

Film editors use a version with a very small overlaps to edit film negatives, although units with a longer overlap are preferred for projection prints.

These can only be used with acetate

Acetate

An acetate is a derivative of acetic acid. This term includes salts and esters, as well as the anion found in solution. Most of the approximately 5 billion kilograms of acetic acid produced annually in industry are used in the production of acetates, which usually take the form of polymers. In...

, triacetate and nitrate

Nitrate

The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically-bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a...

films. Polyester film, such as that used for currently produced prints, will not bond with standard film cement.

Tape splicers

Here a piece of thin transparent adhesive tape is used to join the two ends. The tape may be pre-perforated, or the splicer may make perforations as the splice is made (this type of splicer is sometimes referred to as guillotine splicer).

Tape splicers can be used on all types of film. This is the most popular way to join polyester prints in theaters.

Ultrasonic splicers

These splicers use an ultrasonic signal to melt the film together. They are generally used with polyester film, and are used in splicing microfilm as the splice will not break down over time as a tape splice might.

Thermal paper splicers

Used in film processing labs to join film into large rolls before processing. These use a plastic coated tab to make the splice. The tab is heated and the plastic melts slightly, bonding to the film. The tabs are often printed with a number or bar code to identify the film after processing.