Developer & Fixer Components, Chemical, Agent, & Function

• Sequence of events in processing a radiograph

  1. Wetting

  2. Developing

  3. Rinsing/Stop bath

  4. Fixing

  5. Washing

  6. Drying
• Wetting


  Swells the emulsion to permit subsequent chemical penetration
• Developing


  • Produces a visible image from a latent image
• Rinsing/Stop bath


  • Terminates development and removes excess chemicals from the emulsion
• Fixing


  • Removes remaining silver Halide from the emulsion and hardens gelatin
• Washing


  • Removes excess chemical
• Drying


  • Removes water and prepares radiograph for viewing
• What are the components of developer?

  • Developing Agent
  • Activator
  • Restrainer
  • Preservative
  • Hardener
  • Sequestering Agent
  • Solvent
• Developing Agent


  A component in developer that reduces exposed SHC chemically to black metallic Silver
• Activator


  A component in developer that enhances the action of developing agent, produces alkalinity, and controls pH
• Restrainer


  A component in developer that protects unexposed crystals from chemical attack and decreases fog formation
• Preservative


  A component in developer that controls aerial oxidation and maintains balance among developer components
• Hardener


  A component in developer that controls swelling and softening of the emulsion and enhances archival quality
• Sequestering Agent


  A component in developer that removes metallic impurities and stabilizes developing agent
• Solvent


  A component in developer that dissolves chemicals for use
• What are the components in the fixer?

  Activator

  Fixing Agent

  Hardener

  Preservative

  Buffer

  Sequestering Agent

  Solvent
• Activator- Acetic Acid


  A component and its chemical in fixer that neutralizes the developer and stops its action
• Fixing Agent- Ammonium Thiosulfate

  A component and its chemical in fixer that removes undeveloped silver bromine from emulsion
• Hardener- Potassium Alum


  
  

  A component and its chemical in fixer that stiffens and shrinks emulsion
• Preservative- Sodium Sulfite


  
  

  A component and its chemical in fixer that maintains chemical balance
• Buffer- Acetate


  Component and its chemical in fixer that maintains proper pH
• Sequestering Agent - Boric Acids and Salts


  
  

  
  

  Component and its chemical in Fixer that removes aluminum ion
• Solvent- Water


  Component and its chemical in fixer that dissolves other components
• How much time does drying take in manual and automatic processor?

  Manual: 30 mins

  Automatic Processor: 26 secs
• How much time does washing take in manual and automatic processor

  Manual: 20 mins

  Automatic Processor: 20 secs
• How much time does fixing take in manual and automatic processor?

  Manual: 15 mins

  Automatic Processor: 22 secs
• How much time does rinsing/stop bath take in manual and automatic processor?

  Manual: 30 secs

  Automatic Processor: None
• How much time does developing take in manual and automatic processor?

  Manual: 15 min

  Automatic Processor: 22 secs
• How much time does wetting take in manual and automatic processor?

  Manual: 15 secs

  Automatic Processor: None
• Chemicals of developing agent that:

  Produces Shades of Gray

  Produces Black Tones

  Phenidone

  Elon/Metol

  Hydroquinone
• Chemicals of activator, including other activators used, that: Enhances the action of developing agent (Helps swell gelatin)

  Produces Alkalinity

  Controls pH

  Sodium Carbonate

  Sodium Hydroxide

  Sodium Metaborate

  Sodium Tetraborate
• Chemicals of restrainer that:

  Protects unexposed crystals from chemical Attack

  Decreases fog formation

  Potassium Bromide

  Potassium Iodide
• Chemicals of preservative that:

  Controls aerial Oxidation

  Maintains balance among Developer components

  Sodium Sulfite
• Chemicals of hardener that:

  Controls swelling and softening of the emulsion

  enhances archival quality

  Glutaraldehyde
• Chemicals of Sequestering Agent that:

  Removes metallic Impurities

  Stabilizes developing agent

  Chelates
• Chemical of Solvent that Dissolves chemicals for use

  Water
• Agent and Function of Developing Agent

  Reducing Agents - To reduce exposed SHC chemically to black metallic Silver
• Agent and Functions of Activator

  Buffering Agents -

  • Enhances the action of developing agent (Helps swell gelatin)
  • Produces Alkalinity
  • Controls pH
• Agent and Function of Restrainer

  Anti Fog Agent -

  Protects unexposed crystals from chemical Attack

  Decreases fog formation
• Function of Preservative

  Controls aerial Oxidation

  Maintains balance among Developer components