SIST EN ISO 787-24:1997

General method of tests for pigments and extenders - Part 24: Determination of relative tinting strength of coloured pigments and relative scattering power of white pigments - Photometric methods (ISO 787-24:1985)

The method specified provide an instrumental alternative to those described in ISO 787/16 and ISO 787/17. Equal masses of a coloured material are separately dispersed in the same mass of the same white pigment paste. The reflectivity of each dispersion is measured photometrically. From the corresponding values of K/S the relative tinting strength is given. For measurement of the relative scattering power equal masses of a white test material and an agreed reference pigment are separately dispersed in the same mass of the same black pigment paste. The reflectivity of each dispersion is measured photometrically at 550 nm. From the corresponding values of K/S the relative scattering power is given.

Allgemeine Prüfverfahren für Pigmente und Füllstoffe - Teil 24: Bestimmung der relativen Farbstärke von Buntpigmenten und des relativen Streuvermögens von Weißpigmenten - Photometrische Verfahren (ISO 787-24:1985)

Dieser Teil von ISO 787 beschreibt photometrische Prüfverfahren zum Vergleich a) der Farbstärke zweier ähnlicher Buntpigmente (siehe Anmerkung 1), die ohne Trockenstoffzusatz in einem Alkydharz dispergiert sind und; b) des Streuvermögens zweier Weißpigmente des gleichen Typs, die ohne Trockenstoffzusatz in einem Alkydharz dispegiert sind, im sichtbaren Spektralbereich. Diese Prüfverfahren stellen eine meßtechnische Alternative zuden in ISO 787-16 und ISO 787-17 beschriebenen Verfahren dar, wobei der visuelleVergleich enfällt.

Méthodes générales d'essai des pigments et matieres de charge - Partie 24: Détermination du pouvoir colorant relatif des pigments colorés et du pouvoir diffusant relatif des pigments blancs - Méthodes photométriques (ISO 787-24:1985)

La présente partie de l'ISO 787 décrit des méthodes photométriques
  d'essai pour comparer dans la partie visible du spectre :
a) le pouvoir colorant de deux pigments colorés similaires (voir note
  1) dispersés dans une résine alkyde sans siccatif;
b) le pouvoir diffusant de deux pigments blancs du même type dispersés
  dans une résine alkyde sans siccatif.
Ces méthodes d'essai fournissent une mesure instrumentale en complément
  des méthodes respectivement décrites dans les parties 16 et 17
  de l'ISO 787, évitant la nécessité d'un contrôle
  visuel.
  NOTES:
  1) La présente Norme internationale ne convient pas pour la comparaison
  de pigments colorés dont la couleur en dégradé présente
  d'importants écarts.
  2) Chaque fois que l'une de ces méthodes générales est
  applicable pour un pigment donné, il devra simplement être fait
  référence à la méthode appropriée dans la
  Norme internationale relative à ce pigment, en indiquant, dans une note,
  toutes les modifications de dé

Splošne metode preskušanja pigmentov in polnil - 24. del: Določanje relativne barvne jakosti barvastih pigmentov in relativne moči sipanja belih pigmentov - Fotometrične metode (ISO 787-24:1985)

General Information

• Status: Published
• Publication Date: 30-Nov-1997
• ICS: 87.060.10 - Pigments and extenders
• Technical Committee: PIP - Pigments and extenders
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-1997
• Due Date: 01-Dec-1997
• Completion Date: 01-Dec-1997
• Ref Project: EN ISO 787-24:1995 - General method of tests for pigments and extenders - Part 24: Determination of relative tinting strength of coloured pigments and relative scattering power of white pigments - Photometric methods (ISO 787-24:1985)

Standards Content (Sample)

SLOVENSKI STANDARD
01-december-1997
6SORãQHPHWRGHSUHVNXãDQMDSLJPHQWRYLQSROQLOGHO'RORþDQMHUHODWLYQH
EDUYQHMDNRVWLEDUYDVWLKSLJPHQWRYLQUHODWLYQHPRþLVLSDQMDEHOLKSLJPHQWRY
)RWRPHWULþQHPHWRGH,62
General method of tests for pigments and extenders - Part 24: Determination of relative
tinting strength of coloured pigments and relative scattering power of white pigments -
Photometric methods (ISO 787-24:1985)
Allgemeine Prüfverfahren für Pigmente und Füllstoffe - Teil 24: Bestimmung der relativen
Farbstärke von Buntpigmenten und des relativen Streuvermögens von Weißpigmenten -
Photometrische Verfahren (ISO 787-24:1985)
Méthodes générales d'essai des pigments et matieres de charge - Partie 24:
Détermination du pouvoir colorant relatif des pigments colorés et du pouvoir diffusant
relatif des pigments blancs - Méthodes photométriques (ISO 787-24:1985)
Ta slovenski standard je istoveten z: EN ISO 787-24:1995
ICS:
87.060.10 Pigmenti in polnila Pigments and extenders
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

International Standard 787124
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION.ME~fiYHAPOfiHAR OPTAHM3A~Mfl IlO CTAH~APTbl3A~Mi4.ORGANISATION INTERNATIONALE DE NORMALlSATlOh
General methods of test for pigments and extenders -
Part 24 : Determination of relative tinting strength of
coloured pigments and relative scattering power of white
pigments -
Photometric methods
Mkthodes g&-&ales d’essai des pigments et mat&es de charge - Partie 24 : Dktermina tion du oouvoir colorant rela tif des
pigments color& et du pouvoir diffusant relatif des pigments blancs - Mkthodes ,ohotom&ic&s
Second edition - 1985-12-15
UDC 667.622 : 535.24 : 535.362
Ref. No. IS0 787/24-1985 (E)
Descriptors : paints, pigments, tests, determination, colouring power, photometric method.
- Price based on 11 pages
Foreword
IS0 (the International Organization for Standardization) is a worldwide federation of
national standards bodies (IS0 member bodies). The work of preparing International
Standards is normally carried out through IS0 technical committees. Each member
body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, govern-
mental and non-governmental, in liaison with ISO, also take part in the work.
Draft International Standards adopted by the technical committees are circulated to
the member bodies for approval before their acceptance as International Standards by
the IS0 Council. They are approved in accordance with IS0 procedures requiring at
least 75 % approval by the member bodies voting.
International Standard IS0 787/24 was prepared by Technical Committee ISO/TC 35,
Paints and varnishes.
This second edition cancels and replaces the first edition (IS0 787/24-1982), of which
it constitutes a minor revision.
Users should note that all International Standards undergo revision from time to time
and that any reference made herein to any other International Standard implies its
latest edition, unless otherwise stated.
International Organization for Standardization, 1985
Printed in Switzerland
ii
The purpose of this International Standard is to establish a series of general test
methods for pigments and extenders which are suitable for all or many of the individual
pigments and extenders for which specifications might be required. In such cases, a
cross-reference to the general method should be included in the International Standard
relating to that pigment or extender, with a note of any detailed modification which
might be needed in view of the special properties of the product in question.
Technical Committee ISO/TC 35, Paints and varnishes, decided that all the general
methods should be published as they become available, as parts of a single lnterna-
tional Standard, in order to emphasize the relationship of each to the whole series.
The Technical Committee also decided that, where two or more procedures were wide-
ly used for determining the same or a similar characteristic of a pigment or extender,
there would be no objection to including more than one of them in the IS0 series. In
such cases it will, however, be essential to state clearly in a specification which method
is to be used and, in the test report, which method has been used.
Parts of the series already published are as follows :
Part 1 : Comparison of colour of pigments
Part 2 : Determination of matter volatile at 105 OC
Part 3 : Determination of matter soluble in water - Hot extraction method
Part 4 : Determination of acidity or alkalinity of the aqueous extract
: Determination of oil absorption value
Part 5
Part 7 : Determination of residue on sieve - Water method - Manual procedure
Part 8 : Determination of matter soluble in water - Cold extraction method
Part 9 : Determination of pH value of an aqueous suspension
Part 10 : Determination of density - Pyknometer method
Part 11 : Determination of tamped volume and apparent density after tamping
Part 13 : Determination of water-soluble sulfates, chlorides and nitrates
Part 14 : Determination of resistivity of aqueous extract
Part 15 : Comparison of resistance to light of coloured pigments of similar types
Part 16 : Determination of relative tinting strength (or equivalent colouring value)
and colour on reduction of coloured pigments - Visual comparison method
Part 17 : Comparison of lightening power of white pigments
Part 18 : Determination of residue on sieve - Water method - Mechanical
flushing procedure
Part 19 : Determination of water-soluble nitrates - Salicylic acid method
Part 20 : Comparison of ease of dispersion - Oscillatory shaking method
Part 21 : Comparison of heat stability of pigments using a stoving medium
Part 22 : Comparison of resistance to bleeding of pigments
Part 23 : Determination of density (using a centrifuge to remove entrained air)
Part 24 : Determination of relative tinting strength of coloured pigments and
relative scattering power of white pigments - Photometric methods

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INTERNATIONAL STANDARD IS0 787/24-1985 (E)
General methods of test for pigments and extenders -
Part 24 : Determination of relative tinting strength of
coloured pigments and relative scattering power of white
pigments - Photometric methods
IS0 787, General methods of test for pigments and extenders -
0 Introduction
Part 2 : Determination of matter volatile at 105 OC.
This document is a part of IS0 787, Genera/methods of test for
pigments and extenders.
Part 9 : Determination of ,oH value of an aqueous
suspension.
Part 70 .= Determination of density - Pyknometer method.
1 Scope and field of application
Part 76 : Determination of relative tinting strength (or
This part of IS0 787 describes photometric methods of test for equivalent colouring value) and co/our on reduction of
comparing in the visible spectrum coloured pigments - Visual comparison method.
Part 77 : Comparison of lightening power of white
a) the tinting strength of two similar (see note 1) coloured
pigments.
pigments dispersed in an alkyd resin without a drier;
Part 23 : Determination of density (using a centrifuge to
b) the scattering power of two white pigments of the
remove en trained air).
same type dispersed in an alkyd resin without a drier.
IS0 842, Raw materials for paints and varnishes - Samolinq.
, .
These methods of test provide an instrumental alternative to
IS0 1524, Paints and varnishes - Determination of fineness of
those described in IS0 787/16 and IS0 787/17 respectively,
grind.
avoiding the necessity of visual matching.
IS0 3219, Plastics - Polymers in the liquid, emulsified or
NOTES
Determination of viscosity with a rotational
dispersed state -
1 This International Standard is not appropriate for the comparison of viscometer working at defined shear rate.
coloured pigments that on reduction differ greatly in colour.
IS0 3262, Extenders for paints.
2 When one of these general methods is applicable to a given
pigment, only a cross-reference to the appropriate method should be
IS0 3682, Binders for paints and varnishes - Determination of
included in the International Standard relating to that pigment,
Titrime tric method.
acid value -
indicating any detailed modification which may be needed in view of
the special properties of the product in question. Only when the
appropriate method in this part of IS0 787 is not applicable to a IS0 4629, Binders for paints and varnishes - Determination of
particular product should different photometric methods for
hydroxyl value - Titrime tric method. 1)
determination of relative tinting strength and determination of relative
scattering power be specified.
IS0 4652, Rubber comoounding ingredients - Carbon black
, I
- Determination of specific surface area - Afitrogen
adsoro tion methods.
2 References
IS0 6209, Rubber compounding ingredients - Carbon black
I SO 591, Titanium dioxide pigments for paints. - Determination of solvent extractable material.
-I__-- -.
I) In course of preparation. (Revision of IS0 4629-1978.)
IS0 787/24-1985 (El
32.3 scattering index S,(A) : The spectral scattering co-
3 Definitions
efficient of the pigmented binder divided by the pigment
concentration C, (see 3.1.3) :
For coloured and black pigments
3.1
SW
s,(a) = --- . . . (3)
3.1 .I tinting strength : The ability of a pigment (see the
c,
note) to absorb incident light, thereby having the power to
colour or darken, for example, a white paint in which it is incor-
3.2.4 relative scattering power S,[;1) : The ratio of the scat-
porated.
tering index of the test sample S&) to that of an agreed
reference pigment SD4(A), expressed as a percentage :
NOTE - Although the properties tested are strictly those of the
pigmented binder, absorption and scattering by the binder are rela-
sp3fa)
tively small and it is assumed in this International Standard that the
s,(a) = --- x 100 . . .
(4)
material under test is the dispersed pigment.
sp4( a I
3.3 reflectivity cco : The reflectance of a paste or a paint
3.1.2 spectral absorption coefficient K(A) : The fraction of
film of such thickness that further increase in thickness gives
the diffusely incident spectral radiant flux of wavelength A that
no further change in reflectance.
is absorbed in an elementary layer within a material, divided by
the thickness of the layer (Kubelka-Munk analysis).
according to equation (lo), is
The reflec tivity ,o”,, corrected
related to K/S by the equation
NOTE - KU ) is a measure of the tinting strength of coloured pigmen
in a material and is expressed in units of reciprocal film thickness.
K (1 -&J2
_.-. -.-.-.
. . . (5)
s= 2_0”,
3.1.3 absorbance index K,(1) : The spectral absorption
coefficient of the pigmented binder divided by the pigment
Values of K/S as a function of 100 Q* or 100 R, are given in
concentration C, :
annex B.
NOTES
iv(a)
. . . (I)
1 Kubelka-Munk analysis is strictly applicable only to monochromatic
Kp(a) = c--
n-l
radiation, as indicated in equations (I) to (4). In practice, however, cor-
rect results are often also obtained if the mean value for wider
where C, is the pigment
concentration, for example, ex-
wavebands is taken, as is the case when filters are used. Hence, in the
pressed as the ratio by mass of pigment to binder.
subsequent equations the symbol 3, is omitted.
2 In a dispersion containing a coloured or black pigment and a white
pigment, K is assumed to be characteristic of the coloured or black
3.1.4 relative tinting strength K,(A) : The ratio of the ab-
pigment and S of the white pigment.
sorbance index of the test sample K,t(A) to that of an agreed
reference pigment Kp2(AI, expressed as a percentage :
: The ratio of the radiant flux
3.4 reflectance factor R,
reflected in the directions within a given cone by a paste or a
K,,(A)
K,(A) = -. x 100
. . . (2)
paint film to that reflected in the same directions by a perfect
Kp2( a 1
reflecting diffuser identically irradiated, when the thickness of
the paste or the paint film is such that further increase in
thickness gives no further change in the ratio.
3.2 For white pigments
3.2.1 scattering power : 4 Principle
The ability of a pigment (see the
note to 3.1 .l) to diffuse incident light, thereby having the
power to confer opacity and lightness to, for example, a paint
4.1 Coloured and black pigments
in which it is incorporated.
Equal masses of a coloured pigment p1 and of an agreed
reference pigment p2 are separately dispersed in the same mass
3.2.2 spectral scattering coefficient S(A) : The net transfer
of the same white pigment paste. The reflectivity e,co or the
of spectral radiant flux of wavelength ;1 in the outward direction
reflectance factor R, of each dispersion is measured
from an elementary layer within a body of material illuminated
photometrically at a wavelength giving a minimum value of p_o,
from outside, divided by the product of the thickness of the
or R,. From the corresponding values of K/S, the relative
layer and the difference between the magnitude of the flux in
tinting strength, K,, of the test pigment is given by the equation
the two directions through the layer (Kubelka-Munk analysis).
(Kp,M
KPl
NOTE - Y( 1 ) is a measure of the scattering power of white pigme nts K,= . . .- x lo(-) = -.-. X I()()
. . . (6)
K
in a materia and is expressed in units of reciprocal film thickness. (K,,/S)
P2
IS0 787/24-1985 (El
NOTES
1 The black pigment paste is available commercially. The mixture
K,,/S is the K/S value corresponding to Q~ or R, of the
specified in 5.2.2 is suitable for testing at a pigment volume concen-
test pigment;
tration of 17 % .
K&S is the K
...