ASTM D7772-15(2019)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D7772 − 15 (Reapproved 2019)
Standard Test Method for
Carbon Black Extractables – Absorbance of Cyclohexane
Extract
This standard is issued under the fixed designation D7772; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 4. Significance and Use
1.1 This method covers the determination of extinction
4.1 This procedure serves as a screening process for carbon
(absorbance) of carbon black cyclohexane extract at 386 nm
blacks used in the manufacturing of products that are to come
using a UV spectrophotometer.
into contact with food. The cyclohexane extract absorbance at
386 nm must be less than 0.10 for a 50 mm cuvette in order to
1.2 The values stated in SI units are to be regarded as
fulfill various regulatory requirements.
standard. No other units of measurement are included in this
standard.
5. Apparatus
1.3 This standard does not purport to address all of the
5.1 Spectrophotometer, 20 nm maximum spectral bandpass,
safety concerns, if any, associated with its use. It is the
capable of measuring absorbance at 386 nm.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
5.2 Cuvettes, with an optical light path of 50 mm.
mine the applicability of regulatory limitations prior to use.
5.3 Balance, analytical, sensitivity 0.01 g.
1.4 This international standard was developed in accor-
dance with internationally recognized principles on standard-
5.4 Filter Paper, with a particle retention in liquid less than
ization established in the Decision on Principles for the
2 µm.
Development of International Standards, Guides and Recom-
5.5 Glass Filtering Funnels, 75 mm diameter at top.
mendations issued by the World Trade Organization Technical
5.6 Volumetric Flask, 100 cm .
Barriers to Trade (TBT) Committee.
5.7 Lens Cleaning Tissue, lint free.
2. Referenced Documents
5.8 Timer, with 1 s divisions.
2.1 ASTM Standards:
D4483 Practice for Evaluating Precision for Test Method
5.9 Oven, gravity-convection type, capable of temperature
Standards in the Rubber and Carbon Black Manufacturing regulation of 125 6 5°C.
Industries
5.10 Desiccator.
3. Summary of Test Method
5.11 As a good laboratory practice, it could be suggested the
use of a Neutral Density Filter with a spectral absorbance
3.1 A carbon black sample is gently agitated in cyclohexane
calibrated at 386 nm to ensure the spectrophotometer is
at room temperature to remove any extractable material. The
correctly calibrated.
mixture is left standing in the dark for 24 h at room tempera-
ture. The carbon black is separated from the cyclohexane by
6. Reagents and Materials
filtration, with subsequent determination of the extinction of
the filtrate at 386 nm using a 50-mm cuvette.
6.1 Cyclohexane, analytical reagent grade.
7. Hazards
This test method is under the jurisdiction of ASTM Committee D24 on Carbon
Black and is the direct responsibility of Subcommittee D24.66 on Environment,
7.1 This test involves hazardous materials, operations and
Health, and Safety.
equipment. This procedure does not attempt to address the
Current edition approved Dec. 1, 2019. Published January 2020. Originally
safety problems associated with this test. A hazards review
approved in 2011. Last previous edition approved in 2015 as D7772 – 15. DOI:
10.1520/D7772-15R19.
must be conducted by all personnel performing the test. It is the
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
responsibility of the user to review all MSDS, manuals and
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
hazards procedures and establish the appropriate safety mea-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. sures.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7772 − 15 (2019)
TABLE 1 Precision Parameters for Test Method D7772, Carbon Black Extractables-Absorbance of Cyclohexane Extract (Type 1 Preci-
sion)
Number of Unit Absor-
Material Sr r (r) SR R (R)
Labs bance
N772 4 0.008 0.005 0.015 203.78 0.007 0.020 269.58
N683 (SRB
4 0.011 0.004 0.011 101.72 0.009 0.026 249.15
8F)
Average 0.009
Pooled 0.005 0.013 146.05 0.008 0.024 259.90
8. Calibration, Standardization, and Environmental 9.3 Weigh 1.00 6 0.01 g sample and transfer to a 100 cm
Conditions volumetric flask.
8.1 Standard Laboratory Test Conditions: 9.4 It is imperative that steps 9.5 – 9.9 are carried out in a
8.1.1 Unless stated elsewhere, all testing, calibration and fume hood using disposable nitrile gloves. This kind of gloves
standardization should be carried out in the ambient tempera- are recommended for cyclohexane to prevent skin exposure
ture range of 23 6 3°C. (cyclohexane can cause skin irritation).
8.1.2 The date of calibration or testing should also be
9.5 Add 25 to 30 cm of cyclohexane to the sample flask and
recorded with any relevant data.
stopper the flask.
8.1.3 All calibration data should be recorded on a dedicated
9.6 Shake the mixture gently for a few seconds.
file.
9.7 Fill up to the mark with cyclohexane.
8.2 Instrument Set-Up Frequency – Day of Test:
8.2.1 Turn on the spectrophotometer and allow it to warm 9.8 Close the flask with a stopper, gently shake the mixture
up for 30 min.
again for a few seconds and place it in dark for 24 h at room
8.2.2 Set the wavelength to 386 nm and zero the instrument. temperature.
8.2.3 Place the Neutral Density Filter inside the sample
9.9 After 24 h, filter the mixture through the filter paper and
compartment of the instrument and verify the absorbance value
collect the filtrate in a graduated cylinder. As soon as the
is within the absorbance tolerance. If the filter is found to be
filtration is complete, stopper the graduated cylinder until
outside the limits, verify the filter’s absorbance using a more
ready to test.
sophisticated UV/Vis Spectrometer. If in this case nothing
9.10 Using the same cuvette as described in 8.2.6, rinse and
abnormal is found for the filter, service and calibrate the
fill the cuvette with sample filtrate.
spectrophotometer.
9.10.1 The same cuvette must be used for the blank and all
8.2.4 It is imperative that steps 8.2.5 – 8.2.8 are carried out
samples, as differences in the optical density of different
in a fume hood using disposable nitrile gloves. This kind of
cuvettes will cause errors.
gloves are recommended for cyclohexane to prevent skin
exposure (cyclohexane can cause skin irritation).
9.11 Insert the cuvette into the spectrophotometer and
8.2.5 Filter approximately 50 cm cyclohexane through the
record the absorbance reading obtained at 386 nm.
filter paper in
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D7772 − 15 D7772 − 15 (Reapproved 2019)
Standard Test Method for
Carbon Black Extractables – Absorbance of Cyclohexane
Extract
This standard is issued under the fixed designation D7772; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This method covers the determination of extinction (absorbance) of carbon black cyclohexane extract at 386 nm using a UV
spectrophotometer.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
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.
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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D4483 Practice for Evaluating Precision for Test Method Standards in the Rubber and Carbon Black Manufacturing Industries
3. Summary of Test Method
3.1 A carbon black sample is gently agitated in cyclohexane at room temperature to remove any extractable material. The
mixture is left standing in the dark for 24 h at room temperature. The carbon black is separated from the cyclohexane by filtration,
with subsequent determination of the extinction of the filtrate at 386 nm using a 50-mm cuvette.
4. Significance and Use
4.1 This procedure serves as a screening process for carbon blacks used in the manufacturing of products that are to come into
contact with food. The cyclohexane extract absorbance at 386 nm must be less than 0.10 for a 50 mm cuvette in order to fulfill
various regulatory requirements.
5. Apparatus
5.1 Spectrophotometer, 20 nm maximum spectral bandpass, capable of measuring absorbance at 386 nm.
5.2 Cuvettes, with an optical light path of 50 mm.
5.3 Balance, analytical, sensitivity 0.01 g.
5.4 Filter Paper, with a particle retention in liquid less than 2 μm.
5.5 Glass Filtering Funnels, 75 mm diameter at top.
This test method is under the jurisdiction of ASTM Committee D24 on Carbon Black and is the direct responsibility of Subcommittee D24.66 on Environment, Health,
and Safety.
Current edition approved June 1, 2015Dec. 1, 2019. Published September 2015January 2020. Originally approved in 2011. Last previous edition approved in 20112015
as D7772 – 11.D7772 – 15. DOI: 10.1520/D7772-15.10.1520/D7772-15R19.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7772 − 15 (2019)
5.6 Volumetric Flask, 100 cm .
5.7 Lens Cleaning Tissue, lint free.
5.8 Timer, with 1 s divisions.
5.9 Oven, gravity-convection type, capable of temperature regulation of 125 6 5°C.
5.10 Desiccator.
5.11 As a good laboratory practice, it could be suggested the use of a Neutral Density Filter with a spectral absorbance calibrated
at 386 nm to ensure the spectrophotometer is correctly calibrated.
6. Reagents and Materials
6.1 Cyclohexane, analytical reagent grade.
7. Hazards
7.1 This test involves hazardous materials, operations and equipment. This procedure does not attempt to address the safety
problems associated with this test. A hazards review must be conducted by all personnel performing the test. It is the responsibility
of the user to review all MSDS, manuals and hazards procedures and establish the appropriate safety measures.
8. Calibration, Standardization, and Environmental Conditions
8.1 Standard Laboratory Test ConditionsConditions::
8.1.1 Unless stated elsewhere, all testing, calibration and standardization should be carried out in the ambient temperature range
of 23 6 3°C.
8.1.2 The date of calibration or testing should also be recorded with any relevant data.
8.1.3 All calibration data should be recorded on a dedicated file.
8.2 Instrument Set-Up Frequency – Day of Test:
8.2.1 Turn on the spectrophotometer and allow it to warm up for 30 min.
8.2.2 Set the wavelength to 386 nm and zero the instrument.
8.2.3 Place the Neutral Density Filter inside the sample compartment of the instrument and verify the absorbance value is within
the absorbance tolerance. If the filter is found to be outside the limits, verify the filter’s absorbance using a more sophisticated
UV/Vis Spectrometer. If in this case nothing abnormal is found for the filter, service and calibrate the spectrophotometer.
8.2.4 It is imperative that steps 8.2.5 – 8.2.8 are carried out in a fume hood using disposable nitrile gloves. This kind of gloves
are recommended for cyclohexane to prevent skin exposure (cyclohexane can cause skin irritation).
8.2.5 Filter approximately 50 cm cyclohexane through the filter paper into a stoppered graduated cylinder.
8.2.6 Transfer a portion of the filtered cyclohexane to a clean cuvette. The cuvette should not be handled on the clear working
surface by fingers.
8.2.7 Rinse the cuvette with filtered cyclohexane three times, filling approximately ⁄3 full each time. Discard the rinsing
cyclohexane into an approved safety can.
8.2.8 Fill the cuvette and wipe the outside surfaces with lint free wiping paper while holding the cuvette in front of a suitable
light source to check for smudges. The cyclohexane must be free of any contaminants such as lint particles, which might cause
light scattering and influence test results.
8.2.9 Insert the cuvette into the spectrophotometer, adjust it to read the 386 nm wavelength and zero the instrument to achieve
0.000 absorbance at 386 nm.
9. Procedure
9.1 Dry the sample(s) of carbon black for 1 h at 125 6 5°C prior to testing.
9.2 Allow the sample to cool to room temperature in a desiccator.
9.3 Weigh 1.00 6 0.01 g sample and transfer to a 100 cm volumetric flask.
TABLE 1 Precision Parameters for Test Method D7772, Carbon Black Extractables-Absorbance of Cyclohexane Extract (Type 1 Preci-
sion)
Number of Unit Absor-
Material Sr r (r) SR R (R)
Labs bance
N772 4 0
...