GB/T 38608-2020 PDF in English
GB/T 38608-2020 (GB/T38608-2020, GBT 38608-2020, GBT38608-2020)
| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivered in | Name of Chinese Standard | Status |
| GB/T 38608-2020 | English | 185 |
Add to Cart
|
0-9 seconds. Auto-delivery.
|
Method for determination of the volatile organic compounds (VOCs) content in the ink
| Valid |
Standards related to (historical): GB/T 38608-2020
PDF Preview
GB/T 38608-2020: PDF in English (GBT 38608-2020) GB/T 38608-2020
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 87.080
Y 44
Method for Determination of the Volatile Organic
Compounds (VOCs) Content in the Ink
ISSUED ON: MARCH 31, 2020
IMPLEMENTED ON: OCTOBER 1, 2020
Issued by: State Administration for Market Regulation;
Standardization Administration of the People’s Republic of
China.
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative References ... 4
3 Terms and Definitions ... 4
4 Determination Method ... 5
5 Test Report ... 5
Appendix A (normative) Determination Method of VOCs Content in Ink -
Difference Method ... 7
Appendix B (normative) Determination Method of VOCs Content in Ink - Gas
Chromatography ... 10
Bibliography ... 17
Method for Determination of the Volatile Organic
Compounds (VOCs) Content in the Ink
1 Scope
This Standard specifies the determination method and test report of the volatile organic
compounds (VOCs) content in ink and similar products.
This Standard is applicable to various types of ink and similar products.
2 Normative References
The following documents are indispensable to the application of this document. In
terms of references with a specified date, only versions with a specified date are
applicable to this document. In terms of references without a specified date, the latest
version (including all the modifications) is applicable to this document.
GB/T 3186-2006 Paints, Varnishes and Raw Materials for Paints and Varnishes -
Sampling
GB/T 6283-2008 Chemical Products - Determination of Water Karl Fischer Method
(general method)
GB/T 23993-2009 Determination of Formaldehyde Content of Waterborne Coatings -
Spectrophotometric Method with Acetylacetone
GB/T 32710.10-2016 Safety Requirements for Environmental Testing and Conditioning
Equipment - Part 10: Electric Gravity Convection Ovens and Forced Ventilation Ovens
3 Terms and Definitions
The following terms and definitions are applicable to this document.
3.1 Ink
Ink refers to a dispersion system composed of colorants, binders and auxiliary agents;
a coloring substance that is transferred to the substrate during the printing process.
[GB/T 15962-2018, Definition 2.1]
3.2 Volatile Organic Compounds; VOCs
Appendix A
(normative)
Determination Method of VOCs Content in Ink - Difference Method
A.1 Principle
Weigh-take a certain amount of ink; at a prescribed or agreed temperature, heat it up
to a constant weight. After deducting the moisture content, the lost mass is the content
of volatile organic compounds.
A.2 Equipment
A.2.1 Utensils: aluminum foil box 40 mm 40 mm 10 mm, or, select other suitable
utensils in accordance with the demands.
A.2.2 Blast constant-temperature oven: constant-temperature fluctuation: ± 2 °C. In
order to guarantee the safety of the test, a forced convection oven shall be selected,
and the test shall be performed under secure conditions.
Warning---in order to prevent explosion or fire, samples containing flammable
and volatile substances shall be handled with care and implemented in
accordance with GB/T 32710.10-2016.
A.2.3 Desiccator: with desiccant inside.
A.2.4 Analytical balance: accurate to 0.1 mg.
A.3 Test Methods
A.3.1 Sampling
Sampling shall be performed in accordance with the method specified in GB/T 3186-
2006.
A.3.2 Determination of non-volatile matter content
In the oven, dry the used utensils and paper clips, then, cool them down to room
temperature. Weigh-take a utensil with paper clips, accurate to 0.1 mg. Then, with the
same precision, weigh-take and add around (1.5 ± 0.1) g (or take an appropriate mass
as required) of sample. In addition, disperse the sample as evenly as possible in the
container (in terms of high-viscosity or crust samples, a paper clip may be used to
flatten the sample in the container).
Place the utensil, together with the paper clip, into the oven. At (100 ± 5) °C, heat them
Appendix B
(normative)
Determination Method of VOCs Content in Ink - Gas Chromatography
B.1 Principle
After the sample is processed, adopt the gas chromatography analysis technology to
separate the various volatile organic compounds in the sample. After the test
compounds are qualitatively identified, adopt the internal standard method to
determine its content through the peak area value.
B.2 Instruments and Equipment
B.2.1 Gas chromatograph
B.2.1.1 Split injection system
Gas chromatograph shall have an inlet equipped with a split device. The split ratio shall
be adjustable and able to be monitored.
B.2.1.2 Column thermostat
The temperature range of the column thermostat is 40 °C ~ 300 °C. The column
thermostat shall be able to perform temperature programming. The temperature
fluctuation of the column thermostat shall not exceed 1 °C. The temperature of the
column thermostat shall not exceed the maximum operating temperature of the
chromatographic column.
B.2.1.3 Detector
Any of the following three detectors may be used:
---Flame ionization detector (FID): the maximum working temperature shall not be
lower than 300 °C. The temperature of the detector shall be at least 10 °C
higher than the maximum operating temperature of the column thermostat, so
as to prevent condensation. The gas supply, sample injection volume, split ratio
and gain setting of the detector shall be optimized; the signal (peak area) used
for calculation is proportional to the amount of substance.
---Mass spectrometer or other mass selective detector: already calibrated and
tuned.
---Fourier transform infrared spectrometer (FT-IR spectrometer): already
with the sample component. Within the temperature range of the test, it can be stable,
and its purity is already-known. Solvent-based inks may use N-heptane and N-pentane;
water-based inks may use isobutanol, diethylene glycol dimethyl ether, etc.
B.3.2 Calibration compound
The compound used for calibration shall have a purity of at least 99% by mass fraction,
or an already-known purity.
B.3.3 Dilution solvent
Select a solvent suitable for sample dilution; its purity shall be not lower than 99%, or
an already-known purity. In principle, it shall not contain any impurities that would
interfere with the target substance, for example, substance that causes the peak on
the target compound on the chromatogram to overlap. The injection solvent shall be
separately tested, so as to observe contaminants and possible interference peaks. For
example, offset printing inks use N-hexane and ethanol, etc. Water-based inks may
use methanol, acetonitrile and tetrahydrofuran, etc.
NOTE: if the solvent contains impurities that would interfere with the target substance, a
blank test of the solvent shall be performed; it shall also be deducted when
calculating the VOCs content in the sample.
B.3.4 Marker
A compound with already-known purity and a boiling point of (250 ± 3) °C shall be used
as a marker. In addition, it shall not contain any impurities that would interfere with the
target substance, for example, substance that causes the peak on the target
compound on the chromatogram to overlap.
For example: offset printing inks and water-based inks shall respectively use N-
tetradecane and diethyl adipate as a marker, so as to distinguish organic
compounds with a boiling point lower than or equal to 250 °C.
B.4 Sampling
Sampling shall be performed in accordance with the method specified in GB/T 3186-
2006. Take representative samples for the test.
B.5 Test Procedures
B.5.1 Gas chromatography analysis conditions
B.5.1.1 The adopted gas chromatography analysis conditions depend on the ink to be
analyzed. In addition, already-know calibration mixtures shall be used every time to
optimize it. See the example below.
Example:
Water-based inks
VOCOL column, 60 m 0.32 mm (inner diameter) 1.8 μm (film thickness)
Inlet temperature: 200 °C.
Constant flow mode, column flow 3.0 mL/min, split ratio: 10:1.
Injection volume: 1.0 μL
Temperature-rising program of column thermostat: 40 °C; maintain for 2 min; at the rate of
4 °C/min, raise the temperature to 180 °C, maintain for 15 min.
Detector temperature: 250 °C.
Carrier gas: nitrogen.
Detector gas: hydrogen (H2) and compressed air.
B.5.1.2 Sample injection volume and split ratio shall match each other, so that it does
not exceed the capacity of the chromatographic column and is within the linear range
of the detector. Asymmetric peaks indicate that the gas chromatography system may
be overloaded.
B.5.2 Qualitative analysis
If the organic compound in the product is unknown, then, qualitative identification is
necessary. Use gas chromatograph and mass spectrometer, or other mass selective
detector, or Fourier transform infrared spectrometer (B.2.1.3) in combination. In
addition, adopt the chromatographic operating conditions in B.5.1.
B.5.3 Calibration
B.5.3.1 Under the circumstance where a calibration compound can be obtained, adopt
the following methods to determine its relative correction factor:
a) Accurately weigh-take (accurate to 0.1 mg) the various calibration compounds
qualitatively identified in B.5.2, place them in a sample bottle. The weighed
mass shall be in the same order of magnitude as the content of each
component in the sample to be tested.
b) Weigh-take an internal standard substance that has a similar mass as the
compound to be tested, place it in the same sample bottle. Choose a suitable
diluent to dilute the mixture. Under the same chromatographic operating
conditions as the test sample, determine it. Optimize the instrument
parameters as required.
......
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
|