赤外吸収法による二層フィルムの厚み測定
Thickness Measurements of Two Layer Films by IR
瀬沼昭高・箱崎順一
Senuma, Akitaka / Hakozaki, Jun-ichi
A convenient analysis for the thickness variation of coextruded film has been developed using an infrared absorption with compensator. The following equation was found to be applicable for the ethylene-vinyl acetate copolymer (EVA)/low density polyethylene (LDPE) two-1ayer film ;
(D1740/D1465)(l - lr) (/(d - dr) = K
where D1740 and D1465 are the absorbances of the absorption bands at 1740cm-1 and 1465cm-1, l and lr are the thicknesses of the sample and compensator, d and dr are the EVA layer thicknesses of the sample and compensator, respectively, and K is a constant.
The equation was found to be valid in both cases of the measurements with and without compensator by FTIR.
The thickness variation of EVA/LDPE coextruded films obtained by the above equation shows good agreement with results obtained by the DSC (differential scanning calorimetry) and density measurement method.
Key words: Film thickness variation / Coextruded film / IR / Compensator