ASTM D5531-94(2003)

Standard Guide for Preparation, Maintenance, and Distribution of Physical Product Standards for Color and Geometric Appearance of Coatings

SCOPE
1.1 This guide covers three levels of physical product standards for color commonly used in the coatings industry, provides terminology to describe each level, and describes techniques for generating standards.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.3 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.

General Information

• Status: Historical
• Publication Date: 09-May-2003
• ICS: 87.020 - Paint coating processes
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.26 - Optical Properties

Relations

• Replaces: ASTM D5531-94(1999) - Standard Guide for Preparation, Maintenance, and Distribution of Physical Product Standards for Color and Geometric Appearance of Coatings
• Effective Date: 10-May-2003
• Replaced By: ASTM D5531-05 - Standard Guide for Preparation, Maintenance, and Distribution of Physical Product Standards for Color and Geometric Appearance of Coatings
• Effective Date: 01-Jan-2005
• Referred By: ASTM D3134-15(2019) - Standard Practice for Establishing Color and Gloss Tolerances
• Effective Date: 10-May-2003
• Referred By: ASTM D1729-22 - Standard Practice for Visual Appraisal of Colors and Color Differences of Diffusely-Illuminated Opaque Materials
• Effective Date: 10-May-2003
• Referred By: ASTM D3794-22 - Standard Guide for Testing Coil Coatings
• Effective Date: 10-May-2003
• Referred By: ASTM D7195-21 - Standard Guide for Setting Object Color Specifications
• Effective Date: 10-May-2003
• Referred By: ASTM D3451-06(2017) - Standard Guide for Testing Coating Powders and Powder Coatings
• Effective Date: 10-May-2003

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D5531–94(Reapproved2003)
Standard Guide for
Preparation, Maintenance, and Distribution of Physical
Product Standards for Color and Geometric Appearance of
Coatings
This standard is issued under the fixed designation D5531; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope E430 Test Methods for Measurement of Gloss of High-
Gloss Surfaces by Goniophotometry
1.1 This guide covers three levels of physical product
E805 PracticeforIdentificationofInstrumentalMethodsof
standards for color commonly used in the coatings industry,
Color or Color-Difference Measurement of Materials
provides terminology to describe each level, and describes
E1164 Practice for Obtaining Spectrophotometric Data for
techniques for generating standards.
Object-Color Evaluation
1.2 The values stated in SI units are to be regarded as the
E1331 Test Method for Reflectance Factor and Color by
standard. The values given in parentheses are for information
Spectrophotometry Using Hemispherical Geometry
only.
E1345 Practice for Reducing the Effect of Variability of
1.3 This standard does not purport to address all of the
Color Measurement by Use of Multiple Measurements
safety concerns, if any, associated with its use. It is the
E1347 Test Method for Color and Color-Difference Mea-
responsibility of the user of this standard to establish appro-
surement by Tristimulus (Filter) Colorimetry
priate safety and health practices and determine the applica-
E1349 Test Method for Reflectance Factor and Color by
bility of regulatory limitations prior to use.
Spectrophotometry Using Bidirectional Geometry
2. Referenced Documents
2.2 Society of Automotive Engineers Standard:
SAE J1545 Recommended Practice for Instrumental Color
2.1 ASTM Standards:
Difference Measurement for Exterior Finishes, Textiles,
D16 Terminology for Paint, Related Coatings, Materials
and Colored Trim
and Applications
D523 Test Method for Specular Gloss
3. Terminology
D823 Practices for Producing Films of Uniform Thickness
3.1 The definitions in Terminology E284 and D16 are
of Paint, Varnish, and Related Products on Test Panels
applicable to this test method. The terms in E284 take
D1729 Practice for Visual Appraisal of Colors and Color
precedence over those in D16 if there are differences.
Differences of Diffusely-Illuminated Opaque Materials
3.2 Definitions of Terms Specific to This Standard:
D2244 Practice for Calculation of Color Tolerances and
3.2.1 concept color, n—the color of the material submitted
Color Differences from Instrumentally Measured Color
2 by the customer as the target for generating the master
Coordinates
standard.
D3134 Practice for Establishing Color and Gloss Toler-
2 3.2.2 master standard, n—the physical standard for color
ances
that the customer approves as the target for visual, spectropho-
D4086 Practice for Visual Evaluation of Metamerism
tometric,andcolorimetricevaluationofallproductsreferenced
D4449 Test Method for Visual Evaluation of Gloss Differ-
to that standard.
ences Between Surfaces of Similar Appearance
3.2.2.1 Discussion—in SAE J1545 this is referred to as the
E284 Terminology of Appearance
“official” standard.
E308 Practice for Computing the Colors of Objects by
3.2.3 duplicate master standard, n—a replicate of the mas-
Using the CIE System
ter standard that serves as the master standard at a secondary
location.
1 3.2.3.1 Discussion—in SAE J1545 this is referred to as the
This guide is under the jurisdiction of ASTM Committee D01 on Paint and
“reference” standard.
Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.26 on Optical Properties.
Current edition approved May 10, 2003. Published June 2003. Originally
approved in 1994. Last previous edition approved in 1994 as D5531-94(1999). Available from Society of Automotive Engineers (SAE), 400 Commonwealth
Annual Book of ASTM Standards, Vol 06.01. Dr., Warrendale, PA 15096-0001.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D5531–94 (2003)
3.2.4 working standard, n—the physical product standard introduction of metamerism between the two dissimilar mate-
forcolorusedforroutinemeasurementsandvisualassessments rials far outweighs any possible permanence gains.”
in the laboratory and at the production site.
7. Three Levels of Physical Product Standards for Color
4. Summary of Guide
7.1 Theconceptcolorsubmittedbythecustomershouldnot
4.1 Product standards are the only standards by which
become the master standard because it may be made of
products should be accepted or rejected for color. A master
different material or have gloss or texture (geometric appear-
standard is generated from the concept color submitted by the
ance)differentfromthefinalproduct.Theconceptcolorsimply
customer. Duplicate master standards, when needed, are gen-
represents the customer’s best effort to illustrate the desired
erated from the master standard. Working standards are gener-
color for the coating. The concept color is to be “matched” by
ated from a duplicate master standard. They are used in the
the master standard. The master standard represents the target,
laboratoryorontheproductionlinetoacceptorrejectthecolor
both spectrally and geometrically, for the manufactured coat-
of coatings.After initial generation, product standards must be
ing. It becomes the reference by which the coating is accepted
maintained to ensure that they remain valid. This guide
or rejected. Once the master standard is approved by the
considers the characteristics of product standards, factors to be
customer, the concept color should be filed for possible future
considered in their creation, and factors to be considered in
use.
their replacement.
7.2 The master standard is the reference for judging the
color of duplicate master standards. Although in the case of a
5. Significance and Use
major dispute it is the ultimate reference for color and
5.1 Highqualityphysicalproductstandardsforcolorarethe
geometric appearance, it should not be used for routine
keystone of a successful color control program. Standards are
evaluations in the laboratory or at the production site.
often grouped into three major categories: product standards,
7.3 Duplicate master standards should be prepared at the
intermediate production control standards, and instrument
same time. Duplicate master standards are intended to be
standards. This guide deals only with physical product stan-
identicaltothemasterstandard.Becausetherewillbevariation
dards. Some instrumentally based color control programs use
in perceived or measured characteristics of duplicate master
“numerical standards,” derived from instrumental measure-
standards, buyer and seller must agree on tolerances for
ments of a physical product standard.
“duplicate master standards.” Fairman suggests that the mea-
sured color difference be less than 0.2 CIELAB unit, and
6. Characteristics of Physical Product Standards for
Sherman suggests that the measured color difference be less
Color
than 0.5 FMC-2 unit. SAE J1545 judges standards by stating
6.1 Physical product standards for color should be made of
that the tolerance should be the greater of 0.2 unit in each
the same material as the specimens to be evaluated. This is
CIELAB color difference component, DL*, DC*, and DH*, or
more difficult in the case of coatings because they are not
one-tenth the accepted tolerance for the product (see Practice
usually sold in their final form, that is, they may be sold as a
D3134andE1345).Thenumberofduplicatemasterstandards
liquid or a powder but will end up as a finished film. The
tobemadewilldependuponthelifeexpectancyofthecoloror
coating must be applied to a substrate, usually metal or paper,
product,orboth,thestandard’sresistancetophysicalabuse,its
and cured before evaluation. Agreement must be reached
cleanability, its resistance to color and geometric appearance
between the buyer and the seller on the method of application
change, and the number of times each standard will be used.
and cure for the coating before the master standard is fabri-
7.4 Eachduplicatemasterstandardshouldbegivenaunique
cated.
identification with date of fabrication. A suffici
...