Film Reel Re-spooling and Decarbonization Process: Kodak 5207/5219 ECN-2 Chemical Decarbonization and Development Pitfall Guide

1. The black technology behind film film: What is the graphite carbon layer (Remjet)?

Kodak Vision3 film rolls have extremely high image quality but are only half the price of consumer rolls. The core difference is that there is a black coating on the back of the film:

1. Static electricity crisis in high-speed movie cameras:

• The movie machine mechanically grabs the film at a high speed of 24 frames per second. The high-speed friction of the film between the metal rollers on the guide rail will produce extremely strong static sparks, causing static spark artifacts to explode inside the film;

2. Dual Duty of Black Carbon Black Polymer Coating (Remjet):

• Conductive and antistatic: quickly discharge and conduct away static charges;
• Ultimate anti-halation: completely absorbs all the strong light penetrating the emulsion, preventing the light from hitting the back of the film base and reflecting back to form a red halo;

3. The nightmare of civilian printing shops (one vote to veto):

• Most civilian printing shops use automatic bridge processing machines (such as Noritsu);
• If you mistakenly insert the carbon film roll into the ordinary C-41 potion, the black toner will instantly dissolve and fall off, covering dozens of drive rollers of the entire developing machine, and completely contaminating the expensive potion costing thousands of dollars, causing all subsequent customers' films to be stained with black pits! It is strictly prohibited to conceal the application and send it for reimbursement!

2. Professional ECN-2 alkaline pre-bath (Pre-bath) homemade formula and decarburization process

Home flushing or professional ECN-2 must first perform a pre-bath softening decarburization:

1. Kodak official pre-bath formula (per 1000ml water):

• Anhydrous borax (Borax): 20.0g;
• Anhydrous sodium sulfate (Sodium Sulfate): 100.0g;
• Sodium bicarbonate (baking soda): 10.0g;
• Heat the water temperature to 27℃~38℃;

2. Physical three-step method of decarburization:

• Step 1 (pre-bath infiltration): Inject the pre-bath solution into the rinse tank, shake it gently for 20 seconds, and pour out the pre-bath solution; at this time, the carbon layer is fully softened and expanded by the strong alkali;
• Step 2 (shake vigorously with tap water): Pour in 38°C warm water, close the lid and shake vigorously up and down for 15 seconds, then pour out! At this time the water is dark inky black;
• Step 3 (repeat flushing until the water is clear): Repeatedly pour warm water and shake vigorously 4 to 5 times until the poured water is completely clear, indicating that more than 95% of the toner has been mechanically peeled off!

3. Ultimate anti-scratch, carbon removal and drying after fixation

• Even after development and fixation are completed, trace amounts of microscopic carbon particles may still remain at the edge of the perforations;
• In the final warm water rinse step, pull out the film and soak it in a warm water basin; put on powder-free latex gloves between your index and middle fingers, gently hold the back of the film (glossy film base) under water and apply it smoothly to the bottom to completely take away the remaining toner;
• Do not wipe the emulsion surface with fingernails or dry cloth to prevent scratching the fragile unhardened drug film.

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