ASTM D7489-09(2013)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: D7489 − 09 (Reapproved 2013)
Standard Practice for
Evaluating Touch-Up Properties of Architectural Coatings
under Various Environmental Conditions
This standard is issued under the fixed designation D7489; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope D5069 Practice for Preparation of Paint-Roller Covers for
Evaluation of Architectural Coatings
1.1 This practice determines the ability of a paint to be
D6762 Test Method for Determining the Hiding Power of
recoated or “touched up” in small areas. Variations in color,
Paint by Visual Evaluation of Spray Applied Coatings
gloss, and sheen that result in a different appearance from the
E1347 Test Method for Color and Color-Difference Mea-
original paint can be evaluated visually.
surement by Tristimulus Colorimetry
1.2 This practice describes evaluation of touch-up charac-
teristics in a laboratory-scale controlled environment as op-
3. Terminology
posed to a full-scale field environment.
3.1 Definitions:
1.3 Evaluation of touch-up properties under constant drying
3.1.1 touch-up, n—to repair visual differences in a painted
conditions is described. Environmental conditions can be
surface by recoating small areas with the same paint that was
adjusted to incorporate high or low temperature drying , or
used for the original coat.
both.The changes in application temperature can lead to larger
3.1.1.1 Discussion—This includes color and sheen differ-
differences in touch-up than applying both coats under the
ences in the dry film.
same environmental conditions.
1.4 This standard does not purport to address all of the
4. Summary of Practice
safety concerns, if any, associated with its use. It is the
4.1 Paints, application tools, and drying conditions are
responsibility of the user of this standard to establish appro-
selected before starting this practice. Relevant color(s) for
priate safety and health practices and determine the applica-
testing and any specific primers should also be selected at this
bility of regulatory limitations prior to use.
time.
2. Referenced Documents
4.2 Multiple coats of the test paint are applied to a specified
substrate in a prescribed manner to simulate touch-up condi-
2.1 ASTM Standards:
tions. The results are visually evaluated for variations in color,
D344 Test Method for Relative Hiding Power of Paints by
gloss, and sheen between the touch-up coating and the first and
the Visual Evaluation of Brushouts
second coat.
D523 Test Method for Specular Gloss
D1475 Test Method For Density of Liquid Coatings, Inks,
4.3 A qualitative rating scale for the touch-up result is
and Related Products
described.
D1729 Practice for Visual Appraisal of Colors and Color
Differences of Diffusely-Illuminated Opaque Materials
5. Significance and Use
D5068 Practice for Preparation of Paint Brushes for Evalu-
5.1 During construction of a home, paints are subjected to a
ation
wide variety of drying conditions, and this may exhibit
differences between the original coat and the touched-up area
in appearance after its full cure.Therefore, it it essential for the
This practice is under the jurisdiction of ASTM Committee D01 on Paint and
paint to be able to perform under a wide variety of drying
Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.42 on Architectural Coatings.
conditions. A paint that does this is very advantageous to the
Current edition approved July 1, 2013. Published July 2013. Originally approved
contractor.
in 2009. Last previous edition approved in 2009 as D7489 – 09. DOI: 10.1520/
D7489-09R13.
5.2 Itispossibleforapainttohaveexcellentcolortouch-up,
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
but poor sheen touch-up, or vice-versa. The ideal paint will
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
have both excellent color and sheen touch-up under testing
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. conditions.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7489 − 09 (2013)
5.3 Color,glossandbasechoicecanhaveamajorimpacton 7.2 Select a convenient and suitable spreading rate, mutu-
touch-up of the paint. ally agreeable to all parties involved in the testing program,
and preferably in the range from 8.6 to 11.0 m /L (350 to
6. Apparatus and Materials
450 ft /gal). See Appendix X1 for examples of typical
touch-up applicator and drying conditions.
6.1 Tinted Test Paint.
7.2.1 Results may be highly dependent on film thickness;
6.2 Dry Wall Panels, Upson Board , or other accepted
therefore, it is essential that the test paints be weighed on
material. Minimum size 30 by 30 cm (1 ft by 1 ft).
accurately, particularly for small test areas. The amount of
6.3 Primary Applicator, which could be:
paint in grams required for a specific spread rate can be
6.3.1 Good quality paint roller with ⁄8 in. nap.
determined from the following equation:
6.3.2 Airless spray unit capable of 1000 to 3000 psi and
g 5 ~~Am*D!/Sm!*1000 (1)
appropriate spray tip.
where:
NOTE 1—If using an airless spray unit, typically a larger test panel is
Am = area, square metres,
required.
D = density, g/mL or kg/L, and
6.3.3 Other applicators, as agreed upon.
Sm = spreading rate, square metres/L.
6.4 Secondary Applicator, which could be:
or the following imperial units equation:
6.4.1 Good quality paint roller with 1 cm ( ⁄8 in.) nap.
g 5 A*W /S *3.15 (2)
~~ ! !
6.4.2 Good quality polyester/nylon paint brush.
6.4.3 A natural or synthetic sponge.
where:
6.4.4 Other applicators, as agreed upon.
A = area, sq. in.,
W = weight per gal. (Test Method D1475), lb./gal, and
6.5 Controlled Temperature Drying Area/Cabinet, such as:
S = spreading rate, square ft/gal.
6.5.1 Cold cabinet (refrigerator), maintaining 4 6 2°C (40
NOTE 2—The gallon unit here and throughout this test method is the U.
6 5°F ).
S. gallon (3.78 L).
6.5.2 Constanttemperatureroom,maintaining25 62°C(77
NOTE 3—To avoid variations in initial gloss, the substrate may require
6 5°F).
priming.
6.5.3 May be done in a cabinet maintained at other tem-
7.3 Application of First Coat:
peratures or humidities, or both, as agreed.
7.3.1 The test substrate, applicator for the first coat (appli-
6.6 Gloss Meter (optional), to read gloss differences on test
cator A) and paint are placed in an area (oven, refrigerator, or
panel.
constant temperature room) that corresponds with drying
conditions for first coat (drying conditions A), and allowed to
6.7 Spectrophotometer (optional), to read color differences
equilibrate for at least 4 h.
on test panel.
7.3.2 Applicator is broken in or conditioned for use (for
6.8 Bench Scale (optional), to measure weight of paint
example, Practice D5068 for paint brushes and Practice D5069
applied to test.
for paint rollers).
6.9 Ruler (optional), or other measuring device to measure
7.3.3 Then, one coat of the test paint is applied to the test
area of paint application.
substrate using the applicator A at drying conditions A. An
illustration of the series of three application steps is found in
7. Procedure
Fig. 1. The panel is dried for a minimum of 18 h under drying
7.1 Before starting this method, agree upon paints, tinted conditions A.
color, applicator types for first coat, second coat and touch-up 7.3.3.1 (Optional) — If spread rates are being determined,
area(s), as well as temperature under which each will be measure the weight applied to the test panel using a bench
applied and dried. scale, and measure the length and width of the test area.
FIG. 1 Graphic Representation of First and Second Coats and Touch-up Areas
D7489 − 09 (2013)
7.4 Application of Second Coat: difference is considered very good, whereas major differences
7.4.1 The application of second coat step may be omitted if are considered poor. See rating chart in 9.3.
the critical touch-up being evaluated is directly over a one-coat
8.4 Quantitative Evaluation (optional):
application.
8.4.1 Refer to Test Method D523 for measuring instrumen-
7.4.2 The coated test substrate, applicator for the second
tal gloss values of the panel sections.
coat (applicator B), and paint are placed in an area (oven,
8.4.2 Refer toTest Method E1347 for measuring instrumen-
refrigerator, or constant temperature r
...