|
LABORATORY TEST METHOD NO. H-15
OPACITY OF PLASTIC/PAPER PRODUCTS
1. PURPOSE:
To determine the opaqueness/opacity or "see through"
characteristics of plastic sheeting/films or paper products.
2. PRINCIPLE:
Photo-volt meter is used to measure light reflectance of the
item with a white backing and black backing to differentiate the
"See through" characteristics.
NOTE: The reflectance of plastic/paper is higher when combined
with a white backing than when combined with a black backing
because, in the former case, light transmitted through the
imperfectly opaque material is largely reflected by the white
backing and a portion of the light, thus reflected, is transmitted
through the material a second time.
3. APPARATUS AND MATERIALS:
ASTM D 589-97 (2002) Standard Test Method for Opacity of Paper
ASTM D 2103-03 Standard Specifications for Polyethylene Film and
Sheeting
ASTM D 1746-03 Standard Test Method for Transparency of Plastic
Sheeting
ASTM D 1003-00 Standard Test Method for Haze and Luminous
Transmittance of Transparent Plastics
Photo-volt meter user instructions/manual
4. PROCEDURE:
4.1 Photo-volt meter -Model #575 or equivalent
4.2 Search Unit -Type "Y" Model #04-575-01 or
equivalent
4.3 Opacity Chart Panels (Form 3B) available from Paul N.
Gardner Co., Inc., Pomano Beach, FL
5. EVALUATION:
5.1 Calibrate the photo-volt meter following user's
instructions
5.2 Place plastic/paper material to be tested on the white area
of the opacity chart and adjust the photo-volt meter to read 100.
This will set meter to read light reflected by white background at
100%.
5.3 Place the plastic/paper material on the black area of the
opacity chart sheet and read the reflectance value. This is the
opacity of the sample tested.
6. REPORT
Report the opacity in percent as an average of at least five
readings.
_HARDLINES
TEST METHOD_
|
