X RAY FILMS AND THEIRDEVELOPMENT Presented By AMIT KUMAR ME FINAL YEAR (0708240008)
X RAY FILMS:X ray film is a sheet of plastic (polyester,nitrocellulose or cellulose acetate) coated withan emulsion-gelatin containing light-sensitivesilver halide salts.
X-ray films have two essentialcomponents – Base- Polyester (polyethylene terephthalate resin) 0.2mm thick. Emulsion- Silver halide crystals suspended in gelatin. (0.007- 0.02mm).
Cross section of x-ray film Gelatin super-coat Emulsion base Adhesive Gelatin super-coat
BASECHARACTERISTICS-•Transparent• Flexible• Untearable• Uniform thickness & colour• Impermeable in water & processing solution• Non inflammable• Chemically inactive• Dimensionally stable throughout processing.FUNCTION OF FILM BASE-1) Support for emulsion layer.2) Transmit light to view image.
EMULSIONMicroscopic crystals of silver-bromide & silver iodide suspended in gelatin.Gelatin- treated with mustardoil improves sensitivity of emulsion keeps silver halides uniformly dispersed readily penetrated by processing chemicals and water
Types of films1. Duplitized emulsion films a) Direct exposure (non-screen films) . Intra-oral dental films . Kidney surgery films . Radiation monitoring films b) Screen type films (for use with intensifying screens)
2. Single emulsion filma) Screen type films (for use with single intensifying screens)- Mammography.b) Photoflurographic films- cine films- miniature radiograph.c) Cathode-ray-tube (CRT) photography- USG, CT, MRI.d) Subtraction films.e) Laser imaging film