For additional info on many of these subjects, visit our Youtube channel.
|DART DROP TEST
||Determines resistance to puncturing of the film. Measured in grams. Learn about the ASTM D 1709A test method.|
|DENSITY|| Measure of how closely molecules are packed together. Called out as the number of grams per cubic centimeter. General purpose low density PE films are around .925 gm/cc. Density affects characteristics of film.
Density ranges are as follows:
Low Density Under .929
Medium Density .930 to .940
High Density Over .940
CALORIMETRY (DSC) MELTING POINT
|Used to measure the melting point of plastics. Different test method that vicat softening point, so different values result.|
|Two plies of sheeting wound together.
|DYNE LEVEL||Measure of surface tension. Higher level of surface tension is achieved by passing an electrical charge across the film. The higher the value, the greater the amount of tension. Untreated film has a natural dyne level of about 33. For film to accept adhesive coatings and solvent-based ink for printing, it is necessary to treat film to 38 to 40 dynes. For water-based inks and laminations, a treat level of 45 dynes is required.