Significance and Use
4.1 An important aspect of the appearance of glossy coating surfaces is the distinctness (clarity) of images reflected by them. The values obtained by the measuring procedures given in these methods generally correlate well with visual ratings for DOI (image clarity).
4.2 Although Test Methods D523 and D4039 are useful in characterizing some aspects of glossy appearance, they do not provide satisfactory ratings for DOI (image clarity).
4.3 The measurement conditions given conform to the conditions specified in Test Methods E430.
4.4 The measurement conditions given in Test Methods B and C conform to the conditions specified in ISO 10216.
4.5 The scale values obtained with the measuring procedures of these methods range from 0 to 100 with a value of 100 representing perfect DOI (image clarity).
4.6 The DOI (image clarity) scale value does not of itself, indicate any specific cause for reduction in reflected image sharpness. Surface irregularities such as haze, orange peel, and wrinkle, when present, may be cited as causes for reduction of image sharpness.
1.1 This test method describes the measurement of the distinctness-of-image (DOI) gloss of coating surfaces using electro-optical measuring techniques. The coatings must be applied to planar rigid surfaces. The scale values obtained from the alternative methods cited do not agree.
1.2 Three test methods are covered as follows:
1.2.1 Test Method A—Gloss reflectance factor measurements are made on the specimen at the specular viewing angle and at an angle slightly off the specular viewing angle. The values obtained are combined to provide a DOI value. Very narrow source and receptor aperture angles are used in the measurements.
1.2.2 Test Method B—The light through a small slit is projected on the specimen surface and its reflected image intensity is measured through a sliding combed shutter to provide a value of image clarity.
1.2.3 Test Method C—The light through a pattern is projected on the specimen surface and its reflected image intensity is measured directly to provide a value of image clarity.
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 whoever uses this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D523 Test Method for Specular Gloss
D823 Practices for Producing Films of Uniform Thickness of Paint, Varnish, and Related Products on Test Panels
D2457 Test Method for Specular Gloss of Plastic Films and Solid Plastics
D3964 Practice for Selection of Coating Specimens for Appearance Measurements
D4039 Test Method for Reflection Haze of High-Gloss Surfaces
E284 Terminology of Appearance
E430 Test Methods for Measurement of Gloss of High-Gloss Surfaces by Abridged Goniophotometry
ISO10216 Anodized Aluminum and Aluminum Alloys--Instrumental Determination of Image Clarity of Anodic Oxidation Coatings--Instrumental Method Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
distinctness of image; gloss; high gloss surfaces; image clarity;
ICS Number Code 25.220.01 (Surface treatment and coating in general)
ASTM International is a member of CrossRef.
Citing ASTM Standards
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