Plastics film and sheeting - Determination of thickness by mechanical scanning
1 Scope
This standard specifies a method for the determination of the thickness of a sample of plastics film or sheeting by mechanical scanning.
This standard is not suitable for use with embossed film or sheeting.
2 Apparatus
2.1 Thickness-measuring device
Capable of measuring to the following accuracies:
——up to and including 100 μm to an accuracy of 1 μm (see note 1);
——above 100 μm and up to and including 250 μm to an accuracy of 2 μm;
——above 250 μm to an accuracy of 3 μm.
Note 1: Where the above is not adequate and a higher accuracy is required, this method shall not be applied but a more suitable measuring device or method selected. The determination of gravimetric thickness is described in ISO 4591:1992, Plastics - Film and sheeting - Determination of average thickness of a sample, and average thickness and yield of a roll, by gravimetric techniques (gravimetric thickness).
The measuring surfaces of the device shall comprise a plane lower face and either a plane or radiused upper face. All surfaces shall be polished.
2.1.1 In the case of plane/plane measuring surfaces, the diameter of each face shall be between 2.5 mm and 10 mm and they shall be parallel to within 5 μm. The lower face shall be capable of being adjusted to conform to this requirement. The force applied to the measuring face shall be 0.5 N to 1.0 N.
Foreword i
1 Scope
2 Apparatus
3 Test specimens
4 Procedure
5 Precision
6 Test report
