Lec 4 Processing Solutions

Question 1

Film processing involves the following procedures? (5)

Answer 1

1. Developing
2. Washing
3. Fixation
4. Washing
5. Drying

Question 2

Stage 1: Development
The _____ silver halide crystals in the emulsion are converted by the developer to _____ metallic silver to produce the ___________ parts of the image.

Stage 2: Washing
The film is washed in water to remove residual _____ solution.

Stage 3: Fixation
The _______ silver halide crystals in the emulsion are removed by the fixer to reveal the _______ or _____ parts of the image and the emulsion is _______.

Stage 4: Washing
The film is washed thoroughly in running water to remove residual ____ solution.

Stage 5: Drying
The resultant ____________ radiograph is dried.

Answer 2

• sensitized; black; black/grey
• developer
• unsensitized; transparent/white; hardened
• fixer
• black/white/gray

Question 3

The _________ solution softens the film emulsion.

Answer 3

Developer

Question 4

What are the 2 ingredients of the developer?

Answer 4

Phenidone
Hydroquinone

Question 5

What are the 2 ingredients of the activator?

Answer 5

Sodium hydroxide
Potassium hydroxide

Question 6

Preservative used in the developer solution.

Answer 6

Sodium sulfite

Question 7

Restrainer used in the developer solution.

Answer 7

Bromine-containing compounds

Question 8

Serves as the first electron donor that converts silver ions to metallic silver at the latent image site.

Answer 8

Phenidone

Question 9

Provides an electron to reduce the oxidized phenidone back to its original active state so that it can continue to reduce silver halide grains to metallic silver.

Answer 9

Hydroquinone

Question 10

Maintains an alkaline pH (approximately 10) for activity of developer. Causes the gelatin to swell so that the developing agents can diffuse more rapidly into the emulsion to reach silver bromide crystals.

Answer 10

Activator (sodium hydroxide/potassium hydroxide)

Question 11

Antioxidant that extends life of developing solution. Combines with oxidized developer to produce a compound that subsequently stains images brown if not washed out.

Answer 11

Preservative (sodium sulfite)

Question 12

Restrains development of unexposed silver halide crystals. Acts as antifog agents and increases contrast.

Answer 12

Restrainer (bromine-containing compounds)

Question 13

DEVELOPER REPLENISHER
- Replenished every _____ to prolong life of the used developer.
- __ ounces of fresh developer per gallon of developing solution.

Answer 13

• every morning
• 8 ounces

Question 14

• Dilutes the developer, slowing the development process.
• It also removes the alkali activator, preventing neutralization of the acid fixer.

Answer 14

Rinsing

Question 15

• Removes undeveloped silver halide crystals from the emulsion.
• Hardens and shrinks the film emulsion.

Answer 15

Fixing solution

Question 16

Ingredient of the clearing agent?

Answer 16

Ammonium thiosulfate

Question 17

Ingredient of the acidifier?

Answer 17

Acetic acid

Question 18

Preservative used in the fixing solution.

Answer 18

Ammonium sulfite

Question 19

Hardener used in the fixing solution.

Answer 19

Ammonium sulfate

Question 20

Dissolves the unexposed silver halide grains.

Answer 20

Clearing agent (ammonium thiosulfate)

Question 21

Maintain an acidic pH (approximately 4-4.5). Promotes good diffusion of thiosulfate into the emulsion and of silver thiosulfate complex out of the emulsion.
Inactivates any residual developing agents.

Answer 21

Acidifier (Acetic acid)

Question 22

Prevents oxidation of ammonium thiosulfate, which is unstable in the acidic environment

Answer 22

Preservative (Ammonium sulfite)

Question 23

Complexes with the gelatin during fixing to prevent damage to the gelatin overcoat during subsequent handling.

Answer 23

Hardener (Ammonium sulfate)

Question 24

• __________ = removes unexposed crystals.
• __________ = provides acid medium, aluminum sulfate reacts better in an acid medium, and stops the developing process.
• __________ = prevents deterioration of solution.
• __________ = shrinks and hardens the gelatin.

Answer 24

• fixing agent
• acidifier
• preservative
• hardener

Question 25

• _________ = brings out sharp contrast.
• _________ is now used instead of elon or metol like in other books.
• _________ - It softens and swells the gelatin emulsion and attracts the exposed silver bromide crystals.
• _________ - Slows oxidation and therefore it preserves the strength of the other chemicals; If not present the strength of the other chemicals would rapidly weaken. This explains the darkening of the solution.
• _________ - Restrains the developing agent’s strength. The developing agent will deposit silver in the unexposed crystals in the emulsion causing a silver deposit (fogging) on the film if the restrainer is not added.

Answer 25

• hydroquinone
• phenidone
• activator
• preservative
• restrainer

Question 26

• The processed film is washed in _____ to remove all thiosulfate ions and silver thiosulfate complexes.
• Any silver compound or thiosulfate that remains because of improper washing discolors and causes stains, which are most apparent in the ____________ areas.

Answer 26

• water
• stains
• radiopaque (light)