a. Water Supply. Impurities in water used for mixing solutions cause
To correct these conditions, use
filters to remove impurities or use distilled water.
b. Types of Containers.
Stainless steel, rubber, polyethylene, and
glass are the materials most commonly used for containers for mixing and
c. Cleanliness. Solution contamination during mixing is a common cause
of defective color products. To prevent contamination, all mixing equipment
must be cleaned before and after use.
d. Mixing. Mix the chemical components in the color-processing kits in
the order in which they are used in processing. As each component is mixed
and placed in the container, cover it to protect it against contamination.
Mix color-processing components in water at the
Follow the recommended temperature for each
component as this ensures proper mixing and dissolving of the chemicals.
Proper agitation during mixing is most important.
dissolve the chemicals at the maximum rate, agitate vigorously. However, at
the same time, you must be careful not to introduce excessive amounts of air
into the solution.
The temperature of stored solutions should be monitored
High temperatures can cause oxidation and low temperatures may
cause chemicals to crystallize.
(1) Do not store packaged chemicals or mixed solutions above 140
(2) Avoid freezing the packaged chemicals or mixed solutions.
(3) Processing solutions that are stored in open tanks will have a
longer life if the tanks have floating covers.
(4) For best results, do not use solutions that have been stored
longer than recommended.
When you inspect your finished reversal film and find an error or defect in
the film, you will need to know what caused it.
Figure 4-2 is extremely
helpful when identifying processing faults.