SIST EN ISO 14356:2024

SLOVENSKI STANDARD
01-december-2024
Nadomešča:
SIST EN ISO 14356:2003
Zobozdravstvo - Duplikacijski material (ISO 14356:2024)
Dentistry - Duplicating material (ISO 14356:2024)
Zahnheilkunde – Dublierwerkstoffe (ISO 14356:2024)
Médecine bucco-dentaire - Produits pour duplication (ISO 14356:2024)
Ta slovenski standard je istoveten z: EN ISO 14356:2024
ICS:
11.060.10 Zobotehnični materiali Dental materials
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 14356
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2024
EUROPÄISCHE NORM
ICS 11.060.10 Supersedes EN ISO 14356:2003
English Version
Dentistry - Duplicating material (ISO 14356:2024)
Médecine bucco-dentaire - Produits pour duplication Zahnheilkunde - Dublierwerkstoffe (ISO 14356:2024)
(ISO 14356:2024)
This European Standard was approved by CEN on 13 October 2024.

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 CEN-CENELEC 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 CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 14356:2024 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 14356:2024) has been prepared by Technical Committee ISO/TC 106
"Dentistry" in collaboration with Technical Committee CEN/TC 55 “Dentistry” the secretariat of which
is held by DIN.
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 April 2025, and conflicting national standards shall be
withdrawn at the latest by April 2025.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 14356:2003.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 14356:2024 has been approved by CEN as EN ISO 14356:2024 without any modification.

International
Standard
ISO 14356
Second edition
Dentistry — Duplicating material
2024-10
Médecine bucco-dentaire — Produits pour duplication
Reference number
ISO 14356:2024(en) © ISO 2024
ISO 14356:2024(en)
© ISO 2024
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 14356:2024(en)
Contents Page
Foreword .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Classification by types . 3
5 Material characteristics and properties — Requirements . 4
5.1 General .4
5.2 Melting temperature — Type 1 materials .4
5.3 Pouring temperature — Type 1 materials .4
5.4 Component colours — Type 2 materials .4
5.5 Detail reproduction .4
5.6 Compatibility with refractory investment and, if applicable, gypsum .4
5.7 Elastic recovery .4
5.8 Tear strength.4
5.9 Resistance to fungal growth — Type 1 materials only .4
6 Sampling . 4
7 Test methods — General . 5
7.1 Laboratory conditions .5
7.2 Verification of apparatus function .5
7.3 Specimen preparation and testing . .5
7.3.1 General .5
7.3.2 Preparation of Type 1 materials .5
7.3.3 Preparation of Type 2 materials .5
7.4 Pass/fail determinations .5
7.5 Expression of test results.6
8 Specific specimen preparation and test procedures . 6
8.1 Melting temperature test — Type 1 materials only .6
8.2 Detail reproduction test .6
8.2.1 Apparatus and materials .6
8.2.2 Specimen preparation (three specimens) .7
8.2.3 Test procedure.7
8.2.4 Pass/fail determination and expression of results .7
8.3 Test for compatibility with refractory investment and, if applicable, gypsum .7
8.3.1 Apparatus and materials .7
8.3.2 Specimen preparation .8
8.3.3 Test procedure.9
8.3.4 Pass/fail determination and expression of results .9
8.4 Elastic recovery test .9
8.4.1 Apparatus — Type 1 materials .9
8.4.2 Apparatus — Type 2 materials .9
8.4.3 Apparatus — Type 1 and Type 2 materials .9
8.4.4 Specimen preparation — Type 1 materials (five specimens) .10
8.4.5 Specimen preparation — Type 2 materials (five specimens) .10
8.4.6 Test procedure — Type 1 and Type 2 materials .11
8.4.7 Calculation of results .11
8.4.8 Pass/fail determinations and expression of results . 12
8.5 Tear strength test . 12
8.5.1 Apparatus and materials . 12
8.5.2 Specimen preparation (five specimens) . 13
8.5.3 Test procedure.14
8.5.4 Calculation of results .14
8.5.5 Pass/fail determination and expression of results .14

iii
ISO 14356:2024(en)
8.6 Fungal growth resistance test — Type 1 agar materials only .14
8.6.1 Apparatus and materials .14
8.6.2 Specimen preparation (1 test specimen and 1 control specimen) .14
8.6.3 Test procedure.14
8.6.4 Pass/fail determination .14
8.6.5 Expression of results . 15
9 Requirements for packaging .15
10 Requirements for labelling .15
11 Instructions for use — Required information .15
Annex A (informative) Optional procedure for tear test .26
Bibliography .30

iv
ISO 14356:2024(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO 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,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available
at www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights. Any
trade name used in this document is information given for the convenience of users and does not constitute
an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 106, Dentistry, Subcommittee SC 2,
Prosthodontic materials, in collaboration with the European Committee for Standardization (CEN) Technical
Committee CEN/TC 55, Dentistry, in accordance with the Agreement on technical cooperation between ISO
and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 14356:2003), which has been technically
revised.
The main changes are as follows:
— figures have been updated to be consistent with other impression material related standards;
— terminology, references and document format have been updated.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

v
International Standard ISO 14356:2024(en)
Dentistry — Duplicating material
1 Scope
This document specifies the requirements and tests for the duplicating materials used in dentistry which
are primarily intended for forming flexible moulds needed to produce positive refractory investment copies
of properly blocked-out master models.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 1942, Dentistry — Vocabulary
ISO 6873, Dentistry — Gypsum products
ISO 15912, Dentistry — Refractory investment and die material
ASTM D624-00, Standard test method for tear strength of conventional vulcanized rubber and thermoplastic
elastomers
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 1942 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
double boiler
container system in which the upper container fits into the lower container such that boiling water in the
lower container heats the contents of the lid-covered upper container
3.2
non-reversible duplicating material
material which converts from a pourable consistency to a gel or rubber-like state and which thereafter
cannot be returned to the pourable consistency for repeated use
3.3
effective setting time
time measured from the commencement of mixing components of a material together, or otherwise
activating the chemistry involved, to the time at which the activated material has developed the properties
(elasticity, hardness, etc.) that will permit it to be used with optimal effectiveness in a subsequent step or for
its intended purpose
Note 1 to entry: This applies to materials setting at or near oral or room temperature.

ISO 14356:2024(en)
3.4
functional life
number of times a material can be recycled for use, if handled and used according to the manufacturer’s
instructions, without loss of the properties required to ensure that the material is fit for the purpose
intended
Note 1 to entry: This applies to reversible duplicating material.
3.5
gelation
transition of a material from a relatively fluid consistency to a gel state in which the material has developed
the elastic properties needed for its intended purpose
Note 1 to entry: This applies to agar duplicating material.
3.6
immediate container
packaging component that has internal surfaces in direct contact with the material contained
Note 1 to entry: An immediate container can be an unlabelled container protected by more durable outer packaging,
such as a can, carton or drum. If strong enough to protect its contents without outer packaging, an immediate container
can serve as a primary container on which labelling may be required.
3.7
initial setting time
time measured from the commencement of mixing components of a material or otherwise activating
the chemistry involved and ending at a time when results of a prescribed test, conducted at a specified
temperature, show that the mixture has begun to set, thus indicating that the effective setting time is
reached at some predictable time thereafter
Note 1 to entry: Initial setting times stated in the manufacturer’s instructions are useful to test operators, users, and
standards developers because:
— they can often be used for determining whether a product is of a quality suitable for testing or use. For example, if
the initial setting time found by the test operator or user corresponds closely to that stated in the instructions, it
can usually be assumed that the product is suitable for testing or use.
— they can be helpful in the development of standards for certain materials if there is a need for a standard to
identify a reference point in time that can be used as a basis for specifying when certain subsequent procedures
should begin.
[SOURCE: ISO 1942:2020, 3.3.1.31, modified — Note to entry added.]
3.8
investment
powdered refractory (3.13) containing a binder, to be mixed with a specified liquid to form a slurry that can
be poured into a mould made of duplicating material where it is allowed to harden to form a heat-resistant
positive copy of a master model, or which can be poured around patterns to form a heat-resistant mould
used for forming ceramic or metal objects
Note 1 to entry: This applies to a casting material.
3.9
melt
change a material, by heating, from a gel state to a pourable fluid state
Note 1 to entry: This applies to agar hydrocolloid.

ISO 14356:2024(en)
3.10
outer package
wrapping or carton, used to cover one or more immediate containers (3.6) or primary containers (3.12) in
preparation for retail marketing
Note 1 to entry: Legislation or specific standards can apply.
[SOURCE: ISO 4823:2021, 3.8]
3.11
pouring temperature
temperature of the material designated in the manufacturer’s instructions for pouring the material around
an object to be duplicated
Note 1 to entry: This applies to duplicating material.
3.12
primary container
packaging component for retail marketing which can be covered by an outer package (3.10)
EXAMPLE Bottle, carton, drum, jar, tube, etc.
Note 1 to entry: A primary package can be required to bear specific labelling information by legislation or specific
standard.
Note 2 to entry: A primary container may also be an immediate container (3.6), and vice versa.
3.13
refractory
material that retains its effective shape and composition when heated to the maximum temperature
required for its use
3.14
slurry
mixture, consisting of a powder and water, or a powder and another liquid, that has a consistency that allows
it to be poured around patterns or into moulds, or to be otherwise applied, and then be allowed or caused to
harden so as to form a desired shape
Note 1 to entry: This applies to ceramic, gypsum or investment materials.
3.15
storage
holding of a material in an immediate container (3.6) in a protected environment before the container is
opened for the first use, and between subsequent openings of the container
3.16
store, verb
〈agar hydrocolloid〉 to hold a material at the temperature specified in the manufacturer’s instructions to
keep it at pouring consistency
Note 1 to entry: This applies to agar hydrocolloid.
4 Classification by types
There are two types of duplicating material:
— Type 1: reversible duplicating materials;
— Type 2: non-reversible duplicating materials.

ISO 14356:2024(en)
5 Material characteristics and properties — Requirements
5.1 General
In order to arrive at an objective evaluation of a duplicating material, Clauses 9, 10 and 11 shall be reviewed
before any further steps in the evaluation are begun.
5.2 Melting temperature — Type 1 materials
When tested in accordance with 8.1, the melting temperature shall not exceed the maximum stated in the
manufacturer's instructions [11 c) 2)].
5.3 Pouring temperature — Type 1 materials
The manufacturer's recommended maximum pouring temperature [11 c) 4)] shall not exceed 54 °C.
5.4 Component colours — Type 2 materials
Different components intended for use in the same mixture shall be supplied in contrasting colours in order
to provide a means of determining when the components have been thoroughly mixed.
5.5 Detail reproduction
When tested according to 8.2, the duplicating material shall be in accordance with Figure 1, line b scribed on
the test block, as a positive reproduction, for the full length of the distance between lines d and d , both of
1 2
which shall also be completely reproduced.
5.6 Compatibility with refractory investment and, if applicable, gypsum
When tested in accordance with 8.3, the duplicating materials shall impart a smooth surface to, and separate
cleanly from, the investment or gypsum product poured against it. The investment and gypsum material
poured against the lined surface of the duplicating material specimen shall be in accordance with Figure 1,
line c for the full length of the distance between lines d and d (see Figure 1).
1 2
5.7 Elastic recovery
When tested in accordance with 8.4, the elastic recovery shall be at least 96,50 %.
5.8 Tear strength
When tested in accordance with 8.5, the tear resistance shall be at least 0,3 N/mm for Type 1 materials and
at least 1,0 N/mm for Type 2 materials.
5.9 Resistance to fungal growth — Type 1 materials only
When tested in accordance with 8.6, the specimens shall exhibit no fungal growth.
6 Sampling
Samples of material to be tested shall be procured from a single manufacturing batch as packaged for retail
marketing.
NOTE Amounts of approximately 7,5 l of Type 1 materials and 3,7 l of Type 2 materials are usually enough for
conducting all of the tests and for the considerable practice that can be necessary for the test operator to become
proficient in specimen preparation and testing.

ISO 14356:2024(en)
7 Test methods — General
7.1 Laboratory conditions
Unless otherwise specified in this document, all specimen preparation and testing shall be conducted under
ambient laboratory conditions of (23 ± 2) °C and (50 ± 10) % relative humidity. Unless otherwise specified
in this document, all equipment and materials used in the tests shall be brought to ambient temperature
before use in specimen preparation and testing procedures.
7.2 Verification of apparatus function
Examine all accessories, instruments and equipment before they are used in order to determine whether
they are in acceptable working order. Perform whatever calibration steps are necessary to ensure that the
items are in conformity with the specifications stated for them in this document, or in any related supporting
standard.
7.3 Specimen preparation and testing
7.3.1 General
Unless otherwise specified, prepare and manipulate the materials to be used for forming the test specimens
employing the equipment, and following the procedures, recommended in the manufacturer’s instructions
[see 11 b), 11 c) and 11 d)].
Time the schedules for specimen preparation and testing using a timing device such as a stopwatch accurate
to ±1 s over a 30 s period.
7.3.2 Preparation of Type 1 materials
Use a double boiler for melting Type 1 materials. The amount of melted material prepared for testing
purposes at any one time shall be approximately 700 ml. Melted material remaining after the preparation of
one set of specimens may be used for forming other sets of specimens to be formed and tested on the same
day, provided that the material can be kept at the recommended temperature and consistency for pouring
without re-melting.
7.3.3 Preparation of Type 2 materials
For Type 2 materials, use mass/mass proportioning of the components to be mixed. A volume of
approximately 20 ml shall be prepared for each specimen tested.
7.4 Pass/fail determinations
Unless otherwise specified in this document, the minimum number of specimens required for pass/fail
determinations is either three or five, as indicated by an entry appearing beside the related specimen
preparation or test procedure title.
Unless otherwise specified, the following rules apply:
— For a three-specimen minimum, make and test a series of three specimens initially. If at least two of the
three specimens conform to the related requirement, the material passes. If none conforms, the material
fails. If only one specimen conforms, make three additional specimens. If all three of the additional
specimens conform, the material passes; otherwise the material fails.
— For a five-specimen minimum, make and test a series of five specimens initially. If at least four of the
five specimens conform to the related requirement, the material passes. If only one or two specimens
conform, the material fails. If only three specimens conform, make a series of five additional specimens.
If all five of the second series of specimens conform, the material passes; otherwise the material fails.

ISO 14356:2024(en)
7.5 Expression of test results
Report the number of specimens tested, the number conforming with the specified requirement, and
whether the material passes or fails.
8 Specific specimen preparation and test procedures
8.1 Melting temperature test — Type 1 materials only
8.1.1 Apparatus
8.1.1.1 Ceramic, glass or stainless steel double boiler system which has a component that
accommodates a volume of at least 700 ml of the melted duplicating material.
8.1.1.2 Temperature-measuring device, such as a calibrated 76 mm immersion thermometer which has
graduations of 0,1 °C or equivalent.
8.1.1.3 Heat source, to provide the temperatures needed for the melting process.
8.1.2 Test procedure (one test)
Observe the rate of melting for the specified volume of material (7.3.2). When the material approaches the
final stages of melting, use the device (8.1.1.2) to measure the temperature of the material periodically
until the moment at which the entire volume is free of lumps and granules. Record the temperature for this
occurrence.
8.1.3 Pass/fail determination
Compare the melting temperature recorded in accordance with 8.1.2 with the maximum temperature stated
in the manufacturer's instructions [11 c) 2)]. Then record whether this temperature conforms with the
requirement stated in 5.2.
8.2 Detail reproduction test
8.2.1 Apparatus and materials
8.2.1.1 Test block (see Figure 1).
8.2.1.2 Specimen forming ring mould and ring mould retainer (see Figure 2).
8.2.1.3 Putty-like material for covering external orifices of holes in the ring mould to prevent escape of
the fluid duplicating material.
8.2.1.4 Flat glass or metal plate, approximately 50 mm × 50 mm and at least 3 mm thick.
8.2.1.5 Temperature-conditioning unit (oven, air cooler or water bath), capable of providing an
environment in which the specimen forming assembly (see 8.2.1.1 and 8.2.2.2) can be conditioned to the
temperature specified for the master cast [11 b) 3)] at the time duplicating material is poured against it.
8.2.1.6 Circulating water bath, (for Type 1 materials) set to the temperature specified in the instructions
for cooling the poured duplicating assembly [11 b) 4)].
8.2.1.7 Microscope, capable of ×4 to ×12 magnification and low-angle illumination.

ISO 14356:2024(en)
8.2.2 Specimen preparation (three specimens)
8.2.2.1 Initial preparation
Use a compatible and effective solution in an ultrasonic cleaner to clean the test block (8.2.1.1) prior to each
specimen preparation. Then use the microscope (8.2.1.7) to inspect the lines scribed on the block surface to
verify whether they have been cleared of contaminants.
Seat the ring mould (8.2.1.2) in the recess of the ring-mould retainer and use the putty-like material (8.2.1.3)
to cover the exposed external orifices of the ring mould.
Seat the two assembled parts on the test block to form the specimen forming cavity.
For Type 1 materials, adjust the level of the water in the circulating water bath (8.2.1.6) so that it is
approximately 5 mm below the bottom of the ring-mould retainer when the specimen forming assembly
(8.2.1.1, 8.2.2.2) is placed for cooling.
Then condition this entire assembly, along with the flat plate (8.2.1.4), at the specified temperature (8.2.1.5)
for at least 15 min.
8.2.2.2 Procedure for specimen formation
Immediately after removing the specimen-forming accessories from the temperature-conditioning
environment, begin filling the mould cavity by introducing the fluid duplicating material, at the pouring
temperature specified in [11 c) 4)], along an internal surface of the ring mould. Introduce the fluid so that
the material first enters lines a, b and c (Figure 1) on one side of the test block surface and then flow evenly
in the lines as it moves across to the opposite side of the mould cavity. Slightly overfill the mould cavity and
then, with minimal pressure, push the flat plate down through the excess material and into contact with the
top of the ring mould.
Air-cool the assemblies for Type 1 materials for 5 min and then transfer them to the water bath (8.2.1.6)
for an additional 15 min cooling period. Allow assemblies for Type 2 materials to set for the time and at the
temperature specified in the manufacturer’s instructions [11 b) 4)].
Within 1 min after completing the effective setting or gelation process, separate the duplicating material/
ring-mould assembly from the test block and flush it with distilled or deionized water. Use a gentle air
stream to clear away the remaining surface moisture.
8.2.3 Test procedure
Immediately after clearing moisture from the specimen surface, use the microscope (8.2.1.7) to examine
the specimen for conformity with the requirement specified in 5.5. Complete the examination within 3 min
after separating the specimens from the forming assembly. Then, for Type 1 materials only, re-wet the lined
surface of the specimen to keep it moist pending its use in the compatibility test (8.3).
NOTE Colour differences of the materials can make it necessary to use different light intensities or different colour
filters, or both, when viewing specimens, in order to determine whether the required lines have been reproduced in
surfaces of the duplicating material or to evaluate compatibility with investment or gypsum specimens.
8.2.4 Pass/fail determination and expression of results
Carry out the pass/fail determination and record results in accordance with 7.4 and 7.5
8.3 Test for compatibility with refractory investment and, if applicable, gypsum
8.3.1 Apparatus and materials
8.3.1.1 Detail reproduction test specimens, prepared according to 8.2.2 and found to be in conformity
with 5.5 after examination according to 8.2.3.

ISO 14356:2024(en)
8.3.1.2 Any mould-treating agent that may be recommended in the instructions for treating the
duplicating material mould before an investment or gypsum product is poured into it.
8.3.1.3 Specimen forming slit mould (see Figure 3), with a clamping mechanism, such as worm gear
hose clamp, for use in closing the slit.
Use of the slit mould requires the mould to be clamped so that the slit is closed during the formation of
the investment or gypsum specimen. Later, the clamping force is released to allow the slit to open for
easy removal of the specimen. The brass alloy of which the slit mould is made should therefore have
a strain-at-elastic limit sufficiently high to permit closing and opening of the slit without significant
permanent reduction in its width.
8.3.1.4 Mould-release agent, such as silicone grease, that is non-reactive with the slit mould (8.3.1.3) and
the investment and gypsum products.
8.3.1.5 Refractory investment, in accordance with 11 b) 9).
8.3.1.6 Gypsum product, in accordance with 11 b) 10), if required.
8.3.1.7 Microscope, in accordance with 8.2.1.7.
8.3.2 Specimen preparation
8.3.2.1 General
Prepare three specimens for each different bonding category of investment (8.3.1.5) identified in the
instructions and three specimens for a gypsum product (8.3.1.6), if such a product is identified in the
instructions.
8.3.2.2 Initial preparation
Before using either the investment (8.3.1.5) or gypsum product (8.3.1.6) in the compatibility test, evaluate
each product for conformity with the “setting time” requirement specified in ISO 15912 or ISO 6873. Product
batches which do not conform to the related requirement shall not be used in the compatibility test.
NOTE The “setting time tests” described in ISO 15912 and ISO 6873 are not for determining “final” or “effective”
setting times. Instead they are for determining “initial setting time” as defined in 3.7.
Treat the internal surfaces of the slit mould (8.3.1.3), including the slit surfaces, with a thin film of the
mould-release agent (8.3.1.4) and use the clamping mechanism to close the slit in the mould.
Immediately before separating the duplicating material specimen from the specimen forming assembly,
proportion the ingredients (powder and liquid) to be used to form the investment or gypsum specimen
to the ratio specified in the instructions provided by the manufacturer of the investment or gypsum, in
accordance with ISO 15912 or ISO 6873 [see 11 b) 9) or 11 b) 10)].
8.3.2.3 Procedure for specimen formation
Complete the following three steps within 5 min after completing the examination of the duplicating
material specimen (8.3.1.1) for conformity with the detail reproduction requirement (5.5).
— Seat the specimen, lined surface down, in the recess of the slit mould to form the mould cavity into which
the investment or gypsum material is to be poured.
— Invert the mould cavity assembly and begin mixing the proportioned ingredients.
— Introduce increments of the slurry, via mechanical vibration, into the slit mould along an internal surface,
so as to first cover the ends of the raised lines (a, b, and c in Figure 1) on one side of the specimen surface,

ISO 14356:2024(en)
and then be directed to gradually cover the lines to their opposite ends. Continue adding increments
until the mould is slightly underfilled but not overfilled as a convex surface should be avoided.
At 45 min after the setting time (initial setting time) determined for the investment or gypsum (8.3.2.1),
remove the clamping mechanism from the slit mould and separate the investment or gypsum specimen from
the mould cavity assembly.
8.3.3 Test procedure
Use the microscope (8.3.1.7), with low-angle illumination, to examine the lined surface of the specimen for
conformity with the requirement stated in 5.6 (see Note in 8.2.3).
8.3.4 Pass/fail determination and expression of results
Carry out the pass/fail determination and record results in accordance with 7.4 and 7.5.
8.4 Elastic recovery test
8.4.1 Apparatus — Type 1 materials
8.4.1.1 Specimen forming mould constructed with a polymeric material (see Figure 4).
8.4.1.2 Polymeric ring flask (see Figure 5, Key item 9), such as a segment of plumbing pipe, which has
approximate dimensions of height 35 mm, inside diameter 38 mm and wall thickness 3,7 mm.
8.4.1.3 Glass baseplate, approximately 50 mm × 50 mm and 6 mm thick (see Figure 5, Key item 5).
8.4.1.4 Specimen top-surface-forming plate, a flat polymeric plate approximately 25 mm × 25 mm and
6 mm thick (see Figure 5, Key item 2).
8.4.1.5 Circulating water bath, in accordance with 8.2.1.6.
8.4.2 Apparatus — Type 2 materials
8.4.2.1 Split mould with fixation ring, for forming specimens (see Figure 6).
8.4.2.2 Two glass or metal plates, approximately 50 mm × 50 mm and at least 3 mm thick, to form the
top and bottom surfaces of the specimens.
8.4.2.3 Polyethylene sheets, wrinkle free, approximately 50 mm × 50 mm and 0,035 mm thick (two per
specimen).
8.4.2.4 Mould-release agent, such as silicone grease.
8.4.2.5 C-clamp, which has a minimum screw opening of 40 mm and a minimum throat depth of 30 mm.
8.4.3 Apparatus — Type 1 and Type 2 materials
8.4.3.1 Tem
...