Particle transfer rollers

Fig 12.4 Particle Transfer Roller

Particle Transfer Roller (PTR) cleaners use a slightly sticky urethane coated roller that the dust particles adhere to as the film is wound across them. At least two rollers are required, one for each side of the film, though four rollers are often used.
PTR are really only suitable for loose dirt, such as film dust, and have little or no effect on grease or dirt trapped by grease.

Fig 12.5 Film path on Particle Transfer Rollers

The film wraps at least halfway around each roller to maximise the surface contact (Fig 12.5). Due to the tacky nature of the PTR surface there is a great deal of tension applied to the film as it is wound over the rollers. Consequently film should be immediately rewound at a lower tension if the film is to be returned to storage.

The rollers are washed with soap and water then dried and are ready for use again.

PTR cleaners should not be used with films with flaking emulsion as the adhesive is sufficiently strong to lift the emulsion off the base. If the film being cleaned was decomposing then the rollers should be washed before using on non decomposing films.