Base

- supports the emulsion

- 150-300 mm thick

- semi rigid lucent and made of polyester

- the foundation of the Radiographic Film.

- its primary purpose is to provide a rigid structure unto which the emulsion can be coated

- it is flexible and fracture- resistant

- maintains the film shape and size during use and processing to limit extortion

● Dye- is added to tint the film blue to reduce eye strain.
● Dimensional Stability- is the property of the base to maintain its size and shape.

1. Glass Plate- the original film base


2. Cellulose Nitrate- becomes a substitute of the glass plate and highly flammable


3. Cellulose Triacetate- not flammable and safety base


4. Polyester- more resistant to warping from age and stronger and thinner that cellulose triacetate

Emulsion

- the heart and the most important part of the x-ray film

- this is where the x-rays and light photons from IS interact and transfer information

- consist of homogenous mixture of gelatin and silver halide crystals

- coated evenly in 3-5 µm thick

●The Gelatin provides mechanical support for the silver halide crystals.
● Silver Halide Crystals- the active ingredient of the emulsion. 98% of the crystal is Ag halide crystal and 2% is Ag iodide.

Adhesive Layer

- a thin coating of material between the emulsion and base

- ensures the uniform adhesion between the emulsion and the base

- allows the emulsion and the base to maintain proper contact during use and processing

Overcoat

- the protective covering of the gelatin

- protects the emulsion from scratches, pressure, and contamination during handling, processing and storage

- also allows rough manipulation of film before exposure