
Cellulose
acetate is the generic term used to describe a variety of acetylated
cellulose polymers, including cellulose diacetate, cellulose triacetate
and the mixed esters of cellulose acetate propionate and cellulose
acetate butyrate. Cellulose acetate film softens in acetone and can be
used for duplicating purposes. Acetate films which is wet with acetone
can then be applied to a surface. It is easily removed away from the
object when dry.
Uses: Cellulose Acetate Films and Packaging
Cellulose acetate film is a very versatile general purpose plastic
which is always considered an industry standard in graphic arts,
packaging, printing, overlays, and many other applications. Various
packaging materials used for different purposes are made using these
films. For packaging materials, these films are available in various
finishes like
- Matte
- Clear
- Gel coated (Prepared)
Features
Such films are used for making packaging materials because of their
features like as follows:
- Optical clarity
- Lay Flat
- Printable
- Availability in variety of gauges
Maintenance and Care
Cellulose acetate films may block due to the formation of an adhesive
layer caused as a result of the decomposition reaction. In this reaction
the additive triphenyl phosphate is driven from the base by the
increased acidity and then forms an adhesive bond between the gelatin
layers of the emulsion and backcoat. Care must be taken for this. The
adhesive layer can be dissolved using an ethanol and carrier solution to
remove blocking of the film.
Deterioration of the Film
The deterioration behavior of cellulose films was examined in HCL and
sodium hydroxide solutions of various concentrations to determine acid
and base catalytic effects in heterogeneous systems at room temperature.
With higher concentration, the physical properties of the films changed.
The films recovered after 10 days were slightly opaque and rubbery from
swelling in the solutions before drying. They became brittle and shrank
when dried. The deterioration depended completely on the deacetylation
of cellulose acetate.