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GB 21027-2020 (GB21027-2020)

GB 21027-2020_English: PDF (GB21027-2020)
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GB 21027-2020English305 Add to Cart 0--9 seconds. Auto-delivery Request in common use of security for student’s articles Valid GB 21027-2020

BASIC DATA
Standard ID GB 21027-2020 (GB21027-2020)
Description (Translated English) Request in common use of security for student��s articles
Sector / Industry National Standard
Classification of Chinese Standard Y50
Classification of International Standard 97.180
Word Count Estimation 22,272
Date of Issue 2020-07-23
Date of Implementation 2022-02-01
Older Standard (superseded by this standard) GB 21027-2007
Administrative Organization Ministry of Industry and Information Technology of the People's Republic of China
Proposing organization Ministry of Industry and Information Technology of the People's Republic of China
Issuing agency(ies) State Administration for Market Regulation, National Standardization Administration

Standards related to: GB 21027-2020

GB 21027-2020
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 97.180
Y 50
Replacing GB 21027-2007
Request in common use of security for student's
articles
ISSUED ON: JULY 23, 2020
IMPLEMENTED ON: FEBRUARY 01, 2022
Issued by: State Administration for Market Regulation;
Standardization Administration of PRC.
Table of Contents
Foreword ... 3 
1 Scope ... 6 
2 Normative references ... 6 
3 Terms and definitions ... 7 
4 Requirements ... 7 
5 Test method ... 10 
6 Markings ... 13 
Appendix A (Normative) List of harmful aromatic amines ... 14 
Appendix B (Informative) Design guidelines for the ventilation area of the pen
sleeve ... 15 
Appendix C (Normative) Determination of benzene content in adhesives and
correction products - Gas chromatography ... 17 
Appendix D (Normative) Determination of toluene and xylene content in
adhesives - Gas chromatography ... 20 
Appendix E (Normative) Determination of total volatile organic compounds in
adhesives ... 24 
Appendix F (Normative) Air flow test ... 28 
Appendix G (Informative) Examples of student's articles catalogues and
corresponding requirements ... 30 
Request in common use of security for student's
articles
1 Scope
This standard specifies the requirements, test methods, marking of student's
articles.
This standard applies to learning articles, which are used by students under the
age of 14 (including 14 years old), including watercolor paints, crayons, oil
pastels, colored clay, erasers, correction fluids, correction tapes, correction
stickers, correction pens, liquid glues, solid glue, paste, watercolor pen,
fountain pen, ink ballpoint pen, neutral ink ballpoint pen, water-based ink
ballpoint pen, marker pen, whiteboard pen, highlighter, pencil, mechanical
pencil, ink, lead core, plotter ruler (straightedge, triangle ruler, scale ruler,
protractor, drawing template, excluding T-square), student compasses,
schoolwork books, book covers, school bags, pencil bags, stationery scissors,
stationery boxes, manual pencil sharpeners, pencil sharpeners, utility knifes,
etc.
This standard does not apply to stationery products, which are intended for
students over 14 years old AND are used by professionals.
2 Normative references
The following documents are essential to the application of this document. For
the dated documents, only the versions with the dates indicated are applicable
to this document; for the undated documents, only the latest version (including
all the amendments) is applicable to this standard.
GB/T 606 Chemical reagent - General method for the determination of water
- Karl Fischer method
GB/T 1033.1 Plastics - Methods for determining the density of non-cellular
plastics - Part 1: Immersion method liquid pycnometer method and titration
method
GB/T 2793 Test method for nonvolatile content of adhesives
GB 6675.2-2014 Safety of toys - Part 2: Mechanical and physical properties
4.4.2 Decomposable hazardous aromatic amine dyes are prohibited. The
content of each hazardous aromatic amine shall not exceed 20 mg/kg. See
Appendix A for the list of hazardous aromatic amines.
4.5 Limits of phthalate plasticizers in accessible plastic parts
The total content of three phthalates: dihexyl phthalate (DEHP), dibutyl
phthalate (DBP), butyl benzyl phthalate (BBP), in accessible plastic parts, shall
not exceed 1000 mg/kg. For a single sample, if the sampling size of a single
material is less than 10 mg, it can be exempted.
4.6 The limit of free formic acid in colored clay
The content of free formaldehyde, in the colored clay, shall not exceed 500
mg/kg.
4.7 Brightness (whiteness) of schoolwork books
The brightness (whiteness) of the workbook shall not be greater than 85%.
4.8 Pen sleeve safety
4.8.1 General requirements
The pen sleeve shall meet at least one requirement of 4.8.2 or 4.8.3.
4.8.2 Pen sleeve size
When the pen sleeve enters the ring gauge, which has a diameter of
mm AND a thickness of not less than 19 mm, vertically along the axis, under its
own weight, the length of the pen sleeve, which does not enter the ring gauge,
shall be at least 5 mm.
Note: Pen sleeves, which comply with the requirements of this article, are considered
large enough to not pose a risk of inhalation.
4.8.3 Air flow of pen sleeve
When the maximum pressure difference, at room temperature, is 1.33 kPa, the
air flow through the pen sleeve shall be at least 8 L/min,
Note 1: When the pen sleeve relies on internal ventilation, a round hole which has a
cross-sectional area of about 3.4 mm2 can meet this requirement, BUT multiple small
holes may require a larger total cross-sectional area.
Note 2: Appendix B gives guidelines for pen sleeves relying on external ventilation.
Note 3: Pen sleeves, which comply with the requirements of this article, are considered
not to pose a suffocation hazard.
4.9 Edge, tip
4.9.1 The top of stationery scissors and blades shall be arc tops, not sharp
points.
4.9.2 For stationery scissors, manual pencil sharpeners, pencil sharpeners,
student compasses, plotter rulers, utility knives, etc., if there are functional
sharp edges and sharp points, due to indispensable functionality, it shall provide
warning instructions. There shall be no other non-functional sharp edges and
sharp points.
Note: The writing tip of pencils and similar drawing tools is not considered a dangerous
sharp tip.
4.9.3 The accessible edges, corners or parting lines of stationery boxes, etc.
shall not have sharp burrs, sharp tips or overflows, OR they shall be protected,
so that they cannot be touched.
4.9.4 For the accessible edges of student's articles, including holes and grooves,
they shall not have dangerous burrs or beveled edges, OR use them as folded
edges, curled edges, or formed of curved edges, OR be protected with
permanent protective parts or coatings.
4.9.5 The accessible ends of exposed bolts or threaded rods shall not have
exposed sharp edges or burrs, OR their ends shall be covered with smooth nuts,
so that sharp edges and burrs cannot be touched.
5 Test method
5.1 Limits of migratable elements
The determination of the content of migratable elements shall be carried out, in
accordance with the provisions of GB 6675.4-2014.
5.2 Limits of harmful substances in liquid glue, solid glue, paste
5.2.1 The determination of free formaldehyde content in the adhesive shall be
carried out, in accordance with the provisions of GB/T 32606.
5.2.2 The determination of the benzene content in the adhesive is carried out,
in accordance with Appendix C.
5.2.3 The determination of toluene and xylene content in the adhesive is carried
out, in accordance with Appendix D.
Appendix C
(Normative)
Determination of benzene content in adhesives and correction
products - Gas chromatography
C.1 Overview
This Appendix specifies the determination method of benzene content, in
adhesives and correction products for students.
C.2 Principle
After the specimen is diluted with an appropriate solvent, use a micro-syringe,
to directly inject the diluted specimen solution into the sampling device. Use the
carrier gas to bring it into the chromatographic column, where it is separated
into the corresponding components. Use the hydrogen flame ionization detector,
to detect and record the chromatogram. Use the external standard method, to
calculate the benzene content in the specimen solution.
C.3 Reagents
C3.1 Benzene: Chromatographically pure.
C3.2 Ethyl acetate: Analytically pure.
C.4 Instruments
C.4.1 Injector: Micro-syringe.
C.4.2 Chromatograph: Equipped with hydrogen flame ionization detector.
C.4.3 Chromatographic column: Capillary column; the stationary liquid is
dimethyl polysiloxane.
Note: Where there are other components that are difficult to separate from the peaks
of the tested component, switch to a column, which has a different polarity, to perform
the test, under appropriate conditions.
C.4.4 Recording device: Integrator or chromatography workstation.
C.4.5 The measurement conditions are as follows:
- Vaporization chamber's temperature: 200 °C;
- Testing chamber's temperature: 250 °C;
Appendix D
(Normative)
Determination of toluene and xylene content in adhesives - Gas
chromatography
D.1 Overview
This Appendix specifies the determination method of toluene and xylene
content, in adhesives for students.
D.2 Principle
After the specimen is diluted with an appropriate solvent, directly inject the
diluted specimen solution into the sampling device, by the use of a micro
syringe. Use the carrier gas to bring it into the chromatographic column, where
it is separated into the corresponding components. Use the hydrogen flame
ionization detector, to detect and record the chromatogram. Use the external
standard method, to calculate the content of toluene and xylene, in the
specimen solution.
D.3 Reagents
D.3.1 Toluene: Chromatographically pure.
D.3.2 m-xylene and p-xylene: Chromatographically pure.
D.3.3 o-xylene: Chromatographically pure.
D.3.4 Ethyl acetate: Analytically pure.
D.4 Instruments
D.4.1 Sample injection device: Micro-syringe.
D.4.2 Chromatograph: Equipped with hydrogen flame ionization detector.
D.4.3 Chromatographic column: It shall be able to sufficiently separate the
measured compounds. For example: Polydimethylsiloxane capillary column or
similar models.
Note: When there are other components, which are difficult to separate from the peaks
of the tested component, switch to a column, which has a different polarity, to perform
the test under appropriate conditions.
D.4.4 Recording device: Integrator or chromatographic workstation.
D.4.5 The measurement conditions are as follows:
- Vaporization chamber's temperature: 200 °C;
- Testing chamber's temperature: 250 °C;
- Nitrogen: Purity greater than 99.99%;
- Hydrogen: Purity greater than 99.99%;
- Air: Silica gel to remove water;
- Program heating: Initial temperature 35 °C; holding time 25 min; heating
rate 8 °C/min; ending temperature 150 °C; holding time 10 mm.
Note: Other measurement conditions, which achieve the separation effect, can be
selected.
D.5 Analytical procedures
Weigh 0.5 g ~ 1.0 g (accurate to 0.1 mg) of the specimen. Place it in a 25 mL
volumetric flask. Use ethyl acetate to dissolve and dilute it to the mark. Shake
it well. Use a micro-syringe, to take 1 μL of injected sample. Measure its peak
area. If the peak area of the specimen solution is greater than the peak area of
the maximum concentration in Table D.1, use a pipette to accurately pipette V
volume of the specimen solution, into a 50 mL volumetric flask. Use ethyl
acetate to dilute it to the mark. Shake well before measurement.
D.6 Preparation of standard solution
D.6.1 Preparation of benzene series solution
Toluene, meta-xylene, p-xylene, o-xylene standard solutions: 1.0 mg/mL, 1.0
mg/mL, 1.0 mg/mL.
Respectively, weigh 0.1000 g of toluene, 0.1000 g of m-xylene and p-xylene,
0.1 g of (accurate to 0.1 mg) o-xylene. Place them in a 100 mL volumetric flask.
Use ethyl acetate, to dilute it to the mark. Shake well.
D.6.2 Preparation of series of standard solutions
Add the volume of the standard solution (D.6.1), which is listed in Table D.1,
into six 25 mL volumetric flasks. Use ethyl acetate to dilute it to the mark. Shake
well.
Appendix E
(Normative)
Determination of total volatile organic compounds in adhesives
E.1 Overview
This Appendix is suitable for the determination of total volatile organic
compounds in adhesives for students.
E2 Principle
Put an appropriate amount of adhesive, in a blast drying oven, at a constant
temperature. Determine the total volatile content of the adhesive, within a
specified time. Use Karl Fischer method or gas chromatography, to determine
the water content. The total volatile content of the adhesive is deducted by the
amount of water in it, to calculate the total volatile organic content in the
adhesive.
E.3 Reagents
E.3.1 Unless otherwise specified, only use reagents confirmed to be analytically
pure AND distilled water or deionized water or water of equivalent purity in the
analysis.
E.3.2 Karl Fischer reagent.
E.4 Instruments
E.4.1 Blast drying oven: The temperature is controlled at 105 °C ± 1 °C.
E.4.2 Karl Fischer titrator.
E.4.3 Gas chromatograph: Equipped with thermal conductivity detector.
E.5 Analytical procedures
E.5.1 Determination of total volatile content
Make determination, according to the method specified in GB/T 2793.
E.5.2 Determination of moisture content in adhesive
E.5.2.1 Karl Fischer method
Make determination, according to the method specified in GB/T 606.
E.5.2.2 Gas chromatography
E.5.2.2.1 Reagents
E.5.2.2.1.1 Distilled water.
E.5.2.2.1.2 Anhydrous N,N-dimethylformamide (DMF), analytically pure.
E.5.2.2.1.3 Anhydrous isopropanol, analytically pure.
E.5.2.2.2 Instruments
E.5.2.2.2.1 Gas chromatograph: Equipped with thermal conductivity detector.
E.5.2.2.2.2 Chromatographic column: The column length is 1 m; the outer
diameter is 3.2 mm; the stainless steel column is packed with polymer porous
microspheres of 177 μm ~ 250 μm. (For program heating, the initial column
temperature is 80 °C; the holding time is 5 min; the heating rate is 30 °C/min;
the end temperature is 170 °C; the holding time is 5 min. For the constant
temperature, the column temperature is 140 °C. After the isopropanol is
completely extracted, adjust the column temperature to 170 °C. Wait for the
DMF peak to come out. If the test continues, lower the column temperature to
140 °C.
E.5.2.2.2.3 Recorder.
E.5.2.2.2.4 Micro-syringe.
E.5.2.2.2.5 Glass bottle with stopper: 10 mL,
E.5.2.2.3 Test procedure
E.5.2.2.3.1 Determination of water response factor R
Weigh about 0.2 g of distilled water AND about 0.2 g of isopropanol (accurate
to 0.1 mg). Put it in the same glass bottle with a stopper. Add 2 mL of N, N-
dimethylformamide. Mix well. Use a micro-syringe to inject 1 μL of standard
mixture. Record its chromatogram.
Calculate the water response factor R, according to formula (E.1):
Where:
R - Response factor of water;
mi - The mass of isopropanol, in grams (g);
Appendix F
(Normative)
Air flow test
F.1 Principle
Fully insert the pen sleeve under test into an elastic hose, which has an
appropriate diameter. When air flows through the hose, measure the pressure
difference in two directions, respectively.
F.2 Equipment
F.2.1 Air source: the frequency is not limited; the air supply is at least 25 L/min,
within the pressure range of 4 kPa ~ 50 kPa.
F.2.2 The flow regulator: it can control the flow, which has an accuracy of ± 0.1
L/min.
F.2.3 Flow meter: it is capable of measuring flow in the range of 5 L/min ~ 10
L/min, which has an accuracy of ±0.2 L/min.
F.2.4 Pressure gauge, capable of measuring at least 4.00 kPa pressure, with
an accuracy of ± 0.01 kPa.
F.2.5 Connections and hoses: according to Figure F.1, connect the above
equipment into a test device.
F.2.6 Flexible hose: measure the widest part of the pen sleeve under test; select
the hose, whose inner diameter is 80% ~ 85% of the circumscribed circle
diameter of the pen sleeve under test; its wall thickness is (0.75 ± 0.25) mm;
the Shore hardness A is (55 ± 10).
Note: A hose, which has a diameter suitable for the pen sleeve, may be difficult to
obtain. If necessary, the hose can be manufactured by dip molding technology.
F.3 Procedure
F.3.1 Cut an elastic hose, which has an appropriate length (see F.2.6), so that
when the pen sleeve is inserted and connected to the test device, there is a
loose space at both ends of the pen sleeve. Coat the inner wall of the hose,
with soapy water or other suitable low-viscosity lubricant. The pen sleeve shall
be inserted into the middle of the hose; try to keep it parallel to the axis of the
hose.
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