ASTM D2578-04a
(Test Method)Standard Test Method for Wetting Tension of Polyethylene and Polypropylene Films
Standard Test Method for Wetting Tension of Polyethylene and Polypropylene Films
SCOPE
1.1 This test method covers the measurement of the wetting tension of a polyethylene or polypropylene film surface in contact with drops of specific test solutions in the presence of air.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazards statements are given in Section 8.
Note 1—This test method is equivalent to ISO 8296.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D2578–04a
Standard Test Method for
1
Wetting Tension of Polyethylene and Polypropylene Films
This standard is issued under the fixed designation D 2578; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope* must balance. These forces can be represented by surface
energies acting in the direction of the surfaces and it follows
1.1 This test method covers the measurement of the wetting
that:
tension of a polyethylene or polypropylene film surface in
contact with drops of specific test solutions in the presence of gGL cosu5gGS2gSL (1)
air.
where:
1.2 This standard does not purport to address all of the
u = angle of contact of the edge of the drop with the
safety concerns, if any, associated with its use. It is the
solid surface,
responsibility of the user of this standard to establish appro-
gGL = surface energy of the gas - liquid interface,
priate safety and health practices and determine the applica-
gGS = surface energy of the gas - solid interface, and
bility of regulatory limitations prior to use. Specific hazards
gSL = surface energy of the solid - liquid interface.
statements are given in Section 8.
4.1.1 The right side of the above equation (the difference
NOTE 1—This test method is equivalent to ISO 8296. between the surface energies of the gas - solid and solid -
liquid interfaces) is defined as the wetting tension of the solid
2. Referenced Documents
surface. It is not a fundamental property of the surface but
2
2.1 ASTM Standards:
depends on interaction between the solid and a particular
D 618 Practice for Conditioning Plastics for Testing
environment.
E 691 Practice for Conducting an Interlaboratory Study to
4.1.2 When the gas is air saturated with vapors of the liquid,
Determine the Precision of a Test Method
gGL will be the surface tension of the liquid. If the angle of
2.2 ISO Standard:
contact is 0° the liquid is said to just wet the surface of the
3
ISO 8296
solid, and in this particular case (since cos u = 1) the wetting
tension of the solid will be equal to the surface tension of the
3. Summary of Test Method
liquid.
3.1 In this test method drops of a series of mixtures of
4.2 The ability of polyethylene and polypropylene films to
4
formamide and ethyl Cellosolve of gradually increasing sur-
retain inks, coatings, adhesives, etc., is primarily dependent
face tension are applied to the surface of the polyethylene or
upon the character of their surfaces, and can be improved by
polypropylene film until a mixture is found that just wets the
one of several surface-treating techniques. These same treating
film surface. The wetting tension of the polyethylene or
techniques have been found to increase the wetting tension of
polypropylenefilmsurfacewillbeapproximatedbythesurface
a polyethylene or a polypropylene film surface in contact with
tension of this particular mixture.
mixtures of formamide and ethyl Cellosolve in the presence of
air. It is therefore possible to relate the wetting tension of a
4. Significance and Use
polyethylene or a polypropylene film surface to its ability to
4.1 Whenadropofliquidrestsonthesurfaceofasolid,and
accept and retain inks, coatings, adhesives, etc. The measured
a gas is in contact with both, the forces acting at the interfaces
wetting tension of a specific film surface can only be related to
acceptable ink, coating, or adhesive retention through experi-
ence. Wetting tension in itself is not a completely acceptable
1
This test method is under the jurisdiction ofASTM Committee D20 on Plastics
measure of ink, coating, or adhesive adhesion.
and is the direct responsibility of Subcommittee D20.19 on Film and Sheeting.
Current edition approved Aug. 1, 2004. Published August 2004. Originally
NOTE 2—A wetting tension of 35 dynes/cm or higher has been
approved in 1967. Last previous edition approved in 2004 as D 2578 - 04.
2
generally found to reveal a degree of treatment normally regarded as
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
acceptable for tubular film made from Type 1 polyethylene and intended
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on for commercial flexographic printing. It is, however, possible that some
the ASTM website.
other level of wetting tension may be required to indicate the acceptability
3
Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
of polyethylene films made by other processes, or from other types of
4th Floor, New York, NY 10036.
polyethylene, or intended for other
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.