SIST EN ISO 8254-2:2003

SLOVENSKI STANDARD
SIST EN ISO 8254-2:2003
01-september-2003
Papir, karton in lepenka –Merjenje zrcalnega sijaja – 1. del: 75-stopinjski sijaj z
vzporednim snopom svetlobe, metoda po DIN (ISO 8254-1:2003)
Paper and board - Measurement of specular gloss - Part 2: 75° gloss with a parallel
beam, DIN method (ISO 8254-2:2003)
Papier und Pappe - Bestimmung des Glanzes - Teil 2: Messung mit einem parallelen
Strahl bei 75°, DIN-Verfahren (ISO 8254-2:2003)
Papiers et cartons - Mesurage du brillant spéculaire - Partie 2: Brillant a 75° avec un
faisceau parallele, méthode DIN (ISO 8254-2:2003)
Ta slovenski standard je istoveten z: EN ISO 8254-2:2003
ICS:
85.060 Papir, karton in lepenka Paper and board
SIST EN ISO 8254-2:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 8254-2:2003

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SIST EN ISO 8254-2:2003
EUROPEAN STANDARD
EN ISO 8254-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2003
ICS 85.060
English version
Paper and board - Measurement of specular gloss - Part 2: 75°
gloss with a parallel beam, DIN method (ISO 8254-2:2003)
Papiers et cartons - Mesurage du brillant spéculaire - Partie Papier und Pappe - Bestimmung des Glanzes - Teil 2:
2: Brillant à 75° avec un faisceau parallèle, méthode DIN Messung mit einem parallelen Strahl bei 75°, DIN-
(ISO 8254-2:2003) Verfahren (ISO 8254-2:2003)
This European Standard was approved by CEN on 9 September 2002.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2003 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 8254-2:2003 E
worldwide for CEN national Members.

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SIST EN ISO 8254-2:2003
EN ISO 8254-2:2003 (E)
Contents
Foreword.3
Introduction .4
1 Scope .4
2 Normative references .4
3 Terms and definitions.5
4 Principle.5
5 Equipment.5
5.1 Reflectometer .5
5.2 Gloss standards.5
5.2.1 Zero-gloss standards .6
5.2.2 Primary gloss standards.6
5.2.3 Working standards .6
5.2.4 Intermediate gloss standards.6
6 Sampling.7
7 Preparation of test pieces.7
7.1 Conditioning.7
7.2 Preparation .7
8 Procedure .8
8.1 Calibration .8
8.2 Determination of reflectometer value .8
8.3 Calculation and expression of results.8
9 Test report .9
Annex A (normative) Description of the instrument.10
A.1 Design of the reflectometer value .10
A.2 Properties of the reflectometer.12
A.2.1 Dimensions and tolerances of angles .13
A.2.2 Spectral adaptation.13
A.2.3 Linearity and drift to display.14
A.2.4 Polarization.14
A.3 Test piece-holding device.14
Annex B (informative) Nominated organizations for calibration of intermediate gloss standards .15
Annex C (informative) Bibliography .16
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SIST EN ISO 8254-2:2003
EN ISO 8254-2:2003 (E)
Foreword
This document (EN ISO 8254-2:2003) has been prepared by Technical Committee CEN /TC 172, "Pulp, paper and
board", the secretariat of which is held by DIN, in collaboration with Technical Committee ISO/TC 6 "Paper, board
and pulps".
This European Standard shall be given the status of a national standard, either by publication of an identical text or
by endorsement, at the latest by July 2003, and conflicting national standards shall be withdrawn at the latest by
July 2003.
This Standard contains the following parts:
 Part 1: 75° gloss with a converging beam, TAPPI method
 Part 2: 75° gloss with a parallel beam, DIN method
 Part 3: 20° gloss
In addition, CEN has developed the European Standard EN 14086 "Paper and board - Measurement of specular
gloss - 45° gloss with a parallel beam, DIN-method.
The European Standard EN 14086 and the International Standard ISO/DIS 8254-3 are intended for use with high
gloss papers.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal,
Slovakia, Spain, Sweden, Switzerland and the United Kingdom.
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SIST EN ISO 8254-2:2003
EN ISO 8254-2:2003 (E)
Introduction
Visual gloss is a sensory impression which cannot yet be described completely. Some important physical variables
which influence gloss are however known. The sensory perception of gloss under a suitable illumination results
from a physical stimulus due to reflection of light from a surface. This reflection is defined by an indicatrix which
changes with the angle of incidence. The maximum indicatrix value which is decisive for visual gloss impression is
associated with specular reflection, at an angle of reflection which is approximately equal to the angle of incidence.
The reflectometer value is determined by averaging the reflection in a defined angular region centered in the
specular direction.
NOTE 1 A reflectometer value is a measure of the visual gloss only when the optical conditions of measurement,
such as angles and apertures of illumination and observation are similar to the conditions of viewing.
NOTE 2 Because luminance and structure enter to some extent into the reflectometer value of the test piece, only
the comparison of test pieces with nearly the same luminance and structure is meaningful. The influence of
luminance on the measurement result decreases rapidly with increasing reflectometer value and increasing angle
of reflection.
The proportion of specular reflection in the entire reflection increases with increasing angle of incidence. Very matt
surfaces generate a noticeable degree of specular reflection and, therefore, a noticeable gloss effect only above a
certain minimum angle of incidence. On the other hand, a large angle of incidence reduces the ability to differentiate
between surfaces of high gloss.
NOTE 3 Manufacturers of coated papers usually divide their products into two classes, according to their surface
gloss: matt coating and gloss coating. However, these classes are only defined approximately. The matt class has
reflectometer values, measured according to this European Standard, from 0 to approximately 20. The glossy class
has reflectometer values higher than this value. As there is no precise correlation between reflectometer values
measured with different geometries, it is advisable to compare the reflectometer values only within a single class of
papers and using the same measuring geometry.
This European Standard describes measurement at an angle of incidence of 75° using a parallel beam geometry
commonly known as the 75° DIN method. A second European Standard describes measurement at an angle of 45°
(see EN 14086).
1 Scope
This European Standard specifies a photometric test method for the assessment of visual gloss by means of a
reflectometer value measured at an angle of 75°. It is applicable to plane paper and board surfaces of gloss levels
below 65, measured according to this European Standard. It should be the preferred method for paper and board
surfaces of gloss levels below 20, measured according to this European Standard. Materials containing optical
brightening agents may be measured.
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For
dated references, subsequent amendments to or revisions of any of these publications apply to this European
Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the
publication referred to applies (including amendments).
CIE-Publication No. 38, Radiometric and photometric characteristics.
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SIST EN ISO 8254-2:2003
EN ISO 8254-2:2003 (E)
EN ISO 186, Paper and board — Sampling to determine average quality (ISO 186:1994).
EN 20187, Paper, board and pulps — Standard atmosphere for conditioning and testing and procedure for
monitoring the atmosphere and conditioning of samples (ISO 187:1990).
ISO 10110-5, Optic and optical instruments — Preparation of drawings for optical elements and systems — Part 5:
Surface form tolerances.
3 Terms and definitions
For the purposes of this part of ISO 8254, the following terms and definitions apply.
3.1
indicatrix
angular distribution of the reflected light which is measured as illuminance on the receptor.
3.2
reflectometer
instrument for measuring quantities pertaining to reflection of light.
3.3
reflectometer value
measured variable which, for a given angle of incidence, is proportional to the integral of the reflection indicatrix
within the solid angle defined by the apertures (see Annex A.2.1) and is equal to 100 times the ratio of the value
obtained for the sample to that of a defined specularly reflecting surface (5.2.2).
3.4
specular gloss
reflectometer value as defined in 3.3.
NOTE 1 The defined specularly reflecting surface thus has an assigned reflectometer value of 100. Reflectometer
values are therefore not percentages.
NOTE 2 These definitions are based on definitions in CIE-Publication No. 17.4.
4 Principle
The sample is illuminated with a collimated beam at an angle of 75 ° to the normal, and the reflectometer value is
measured within a solid angle defined by a given aperture at an angle of reflection equal to the angle of incidence.
The scale of the reflectometer is calibrated with reference to the reflection from a black glass plate or a quartz
wedge with a specific refractive index.
5 Equipment
5.1 Reflectometer
The reflectometer shall consist of the following principal components: a collimator, a decollimator, an electric supply
for the light source device, a photoelectronic receptor and a sample holder, as described in annex A.
5.2 Gloss standards
The reflectometer is calibrated by means of a zero-gloss standard and a high gloss standard with a reflectometer
value between about 80 and 100. This high gloss standard can be either a primary gloss standard or a working
gloss standard.
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SIST EN ISO 8254-2:2003
EN ISO 8254-2:2003 (E)
Intermediate gloss standards with assigned reflectometer values are used to check the adjustment of the device.
NOTE As reflectometer values of gloss standards may change due to environmental influences, they should be
checked at least once per year.
5.2.1 Zero-gloss standards
A zero-gloss standard is a gloss standard which, in the ideal case, absorbs all light falling on it. A black cavity lined
with black velvet or felt is one realisation of such a gloss standard that has been proven in practice.
5.2.2 Primary gloss standards
A primary gloss standard is a gloss standard whose reflectometer value can be calculated by means of its
refractive index using the Fresnel equation. The reflectometer value is defined as being equal to 100 for a black
glass plate or a fused quartz wedge with a nominal refractive index of n = 1,567 at a wavelength of 587,6 nm (He-d-
line). A black glass plate or quartz wedge with a refractive index at a wavelength of 587,6 nm (see ISO 7944)
known to 3 decimal places can be used as primary gloss standard. The top surface of the glass plate or quartz
wedge shall be plane to within 2 fringes per centimetre as measured by an optical interference method in a
wavelength region of (600 ± 100) nm according to ISO 10110
...