2. Radiographic film is a device sandwich between the
radiographic intensifying screen in a protective cassette.
it is a device which help us to to record the information
regarding the object through which the x rays passes & hence
they greatly help in diagnosis, and treatment of the patient
problem.
3. The first x rays were recorded on glass plates. These were
coated with emulsion on one side only.
During WWI , nitrocellulose based films was found.(single
emulsion).
It was later discovered double emulsion.
In 1924, cellulose acetate replaced the nitrocellulose based
film.
4. There are four layers present in the radiographic film—
a) Base layer.
b) Adhesive layer.
c) Emulsion layer.
d) Protective layer
5.
6. This is the foundation of the film.
Thickness is 0.18mm
Provides a surface and support for emulsion.
Consists of polyester, polyethylene, terephthalate, resin are used.
Transmit light.
It is flexible , thick and strong
7. Also called subbing layer or substratum layer.
Made of mixture of gelatin solution and solvent of film base.
It keep emulsion layer and base adhered to each other.
8. It is known as active layer of film.
It also known as heart of radiographic film.
It is consists of a homogenous mixture of gelatin and silver halide such as
AgBr and AgI .
In typical emulsion 90-99% is AgBr and about 1-10% is AgI. (AgI more
sensitive than AgBr)
9. Thin layer of Gelatin.(derived from animal tissue and is a form of collagen)
Protect the emulsion from mechanical damage.
Reduces damages from pressure, handling and processing.