Powered by Google www.ChineseStandard.net Database: 189760 (20 Apr 2024)

GB/T 26398-2017 (GBT26398-2017)

GB/T 26398-2017_English: PDF (GBT 26398-2017, GBT26398-2017)
Standard IDContents [version]USDSTEP2[PDF] delivered inStandard Title (Description)StatusPDF
GB/T 26398-2017English260 Add to Cart 0--9 seconds. Auto-delivery Evaluation guide of detergence, water costing and saving for laundry detergents -- Simulated household washing test method Valid GB/T 26398-2017

Standard ID GB/T 26398-2017 (GB/T26398-2017)
Description (Translated English) Evaluation guide of detergence, water costing and saving for laundry detergents -- Simulated household washing test method
Sector / Industry National Standard (Recommended)
Classification of Chinese Standard Y43
Classification of International Standard 71.100.40
Word Count Estimation 18,189
Date of Issue 2017-12-29
Date of Implementation 2018-07-01
Drafting Organization China Daily Chemical Industry Research Institute [National Detergent Quality Supervision and Inspection Center (Taiyuan)], Xi-An Kai Co., Ltd., Guangzhou Blue Moon Industrial Co., Ltd., Beijing Green umbrella Chemical Co., Ltd., Beijing Luohua Daily Chemical Co., Ltd.
Administrative Organization National Surfactants and Detergents Standardization Technical Committee (SAC/TC 272)
Proposing organization China National Light Industry Council
Issuing agency(ies) People's Republic of China General Administration of Quality Supervision, Inspection and Quarantine, China National Standardization Administration

Standards related to: GB/T 26398-2017

GB/T 26398-2017
ICS 71.100.40
Y 43
Replacing GB/T 26398-2011
Evaluation Guide of Detergence, Water Costing and
Saving for Laundry Detergents - Simulated Household
Washing Test Method
Issued by: General Administration of Quality Supervision, Inspection and
Standardization Administration of the People’s Republic of
Table of Contents
Foreword ... 3 
Introduction ... 4 
1 Scope ... 6 
2 Normative References ... 6 
3 Terms and Definitions ... 6 
4 Basic Principles ... 8 
5 Sample Preparation ... 8 
6 Selection of Washing Materials and Stains ... 8 
7 Water Quality and Temperature ... 9 
8 Modes of Washing ... 10 
9 Process of Washing ... 10 
10 Determination Indexes ... 11 
11 Evaluation of Washing Performance ... 14 
12 Evaluation of Level of Using Water and Water-saving Performance ... 16 
13 Number of Test Repetitions ... 16 
14 Test Personnel and Environment ... 17 
15 Test Report ... 17 
Appendix A (normative) Selection Principles, Quality Requirements and Types
of Stained Cloth Pieces Used in Detergency Test ... 18 
Appendix B (informative) Common Methods for Detection of Physical and
Chemical Indicators in Rinse Solution ... 23 
Appendix C (informative) Format of Test Record ... 25 
Bibliography ... 27 
Evaluation Guide of Detergence, Water Costing and
Saving for Laundry Detergents - Simulated Household
Washing Test Method
1 Scope
This Standard provides basic principles, basis and modes, as well as conditions that
need to be determined for the establishment of evaluation methods for the detergency,
whiteness preserved, level of using water and water-saving performance of test
laundry detergents through the simulated household washing mode under laboratory
This Standard is applicable to all types of laundry detergents (excluding soap products)
with water as the wash solution.
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 13173-2008 Surface Active Agents - Detergents - Testing Methods
GB/T 13174 Determination of Detergency and Cycle of Washing Property for Laundry
3 Terms and Definitions
The following terms and definitions are applicable to this Standard.
3.1 Wash
Wash refers to the process of removing stains adhering to clothes with an aqueous
solution containing detergent.
NOTE: the aqueous solution containing detergent used in washing is known as wash
3.2 Rinse
Rinse refers to the process of adding water to rinse clothes after washing.
number (in the calculation, the level of using water is calculated by the sum of water
used for rinsing).
3.9 Saving Water
Saving water refers to the degree of reduction in the level of using water of the sample
detergent relative to the reference detergent after the completion of washing under
determined washing comparison conditions.
4 Basic Principles
4.1 Under laboratory conditions, the determined washing and rinsing methods shall be
able to reflect the consumers’ actual washing habits.
4.2 The determined evaluation indexes shall be suitable for the washing characteristics
of the type of detergent.
4.3 The test result of the evaluation shall manifest a certain degree of reproducibility.
5 Sample Preparation
The test samples may come from organizations or individuals that have test demands,
such as: manufacturers, markets and consumers, etc. In order to make the sample test
results comparable and reproducible, some reference detergents with fixed formulas
may be used for comparison, for example, the standard detergent specified in GB/T
13174 may be considered as the basis for determining the washing performance and
the level of using water of the sample.
The sample treatment and application shall comply with the stipulations of Chapter 4
in GB/T 13173-2008.
6 Selection of Washing Materials and Stains
6.1 Washing Lining (companion washing fabric)
The selection of washing fabrics for tests needs to consider the suitability with the
determination of the evaluation results of the level of using water of the detergent. It
shall also be close to the ratio of the mainstream fabrics in the market. Since different
fabrics have different adsorption of laundry detergents, it is relatively reasonable to use
a combination of fabrics with various typical materials for the washing tests. This
combination may refer to the ratio of various fabrics worn by consumers daily. In
addition, in accordance with the washing requirements, determine the quality of the
fabrics to be washed at an appropriate quality. In the evaluation of the mode of washing
by washing machines, use a set of washing lining fabrics with a net weight of 1,300 g
In real life, the temperature of water used for washing significantly varies in different
regions and seasons. The common washing temperature is the natural water
temperature. In the test, the temperature of water used for washing is also a condition
that needs to be controlled by the test personnel. Just like the water quality, within the
range of 10 °C ~ 30 °C, selecting different temperature points for the washing test can
reflect the performance of the detergent in a more comprehensive way. The typical test
temperature is 25 °C ± 2 °C.
8 Modes of Washing
There are three modes of washing: washing by washing machines (machine washing),
manual washing (hand washing) and manual and machine washing. The third mode is
mainly used as a supplement to the first mode, and the level of using water in actual
washing is the same as that of the first mode, which depends on the set program of
the washing machine. Therefore, the design of washing test may be carried out through
the mode of machine washing or hand washing. Starting from the fundamental purpose
of the test to explore the performance of the detergents, the determined washing mode
shall have a certain degree of reproducibility based on the simulated washing mode in
real life. For this reason, adopting the mode of machine washing makes it easier for
the reproductivity of the test results.
For the mode of machine washing, the soaking, washing, drying and rinsing links, and
the level of using water may be determined in accordance with the program set by the
machine. In addition, they shall remain unchanged throughout the test, so as to obtain
stable, comparable and reproducible test results. During the washing test, in order to
monitor the water quality changes of the wash solution at any time, the two-cylinder
washing machine may be more convenient than the fully automatic washing machine.
The test result of washing by washing machine has a high degree of consistency with
the actual washing result, but it is not easy to control the test error and cost. Another
alternative is to use the mode of simulating the laboratory detergency test machine for
evaluation. This method has advantages in the repeatability control of the test results
and the test cost, but its conformity with the reality may be relatively low.
For the mode of hand washing, the implementer of this Standard needs to further
specify the details of washing, wringing and rinsing, including the size of the washtub
and the amount of water added each time, etc. In addition, the operating personnel
shall receive uniform trainings, so as to ensure that the difference in the results
obtained by different operators are within the acceptable range.
9 Process of Washing
9.1 Detergency
After determining the test conditions of washing, enter the actual washing. Whether it
standards and literature, select the method that complies with the requirements of the
detection limit and precision. Appendix B lists some commonly used detection methods
for selection.
10.3 Application of Determination Indexes
For the determination of the rinsing effect, appropriate indexes shall be selected from
the indexes listed in Table 1 to determine each rinse solution. The indexes selected for
the tests should be involved in all three categories; they are also related to the formula
of the detergent (for example, if an anionic surfactant is not added, then, it is
unnecessary to test the indexes related to anionic surfactants) and can objectively
reflect the rinsing effect.
The judgment of the end of rinse is determined by comparing the variation trend of the
same type of indexes in the adjacent rinse solution. When the index of a certain rinse
(the ith rinse) is significantly different from the same index of the previous rinse, while
the relative change of the index of the following rinse is not obvious, then, it can be
considered that the ith rinse has reached the actual demands, and the rinse can be
terminated. In the specific test, the index of the ith rinse can be used as the base
number to estimate the change ratios Ni-1 and Ni+1 of the indexes of the (i - 1)th rinse
and the (i + 1)th rinse, so as to make the judgment of the rinsing result.
NOTE 1: the principle of determining the number (i) of rinses is that Ni-1 larger than 1, and
Ni+1 smaller than 1 and close to 1. When Ni-1 is much larger than 1, and Ni+1 is
much smaller than 1, it indicates that the rinse of the detergent needs to be
continued, and that it needs to be re-calculated and re-evaluated in accordance
with the data after the end of the next rinse.
NOTE 2: the deviation of the value of N from 1, and the difference between Ni-1 and Ni+1
are related to specific indexes. For different indexes, the magnitude of changes
of the value of N is different. For some indexes (for example, anionic surfactant
content), there may be an order of magnitude changes in the value of N; for some
other indexes (for example, pH), the magnitude of changes of the value of N is
relatively small; for some non-digital characterized items (such as: foam and
turbidity), the value of N is based on manual estimation. The implementer of this
Standard may combine the characteristics of the test samples and the indexes
to determine the acceptable range of the value of N during the evaluation of rinse.
For the non-digital characterized items, a mode of estimating the value of N shall
also be drawn up (for example, the amount of foam on the liquid surface of the
solution or the size of foam on the liquid surface may be chosen as the basis for
calculation; for the turbidity of the solution, unused rinse solution may be used
as a benchmark for comparison).
NOTE 3: in order to effectively apply the value of N, the standard detergent listed in GB/T
13174 should be used for confirmation tests; the reference basis for the
application of the value of N of each index in the laboratory shall be established.
whiteness value F2 of the test piece after washing.
NOTE: use whiteness meter that complies with the stipulations of JB/T 9327 and JJG 512.
The whiteness meter method is applicable to the evaluation of stains mainly in
black and white. For detergents added with fluorescent brighteners, different types
of whiteness meters (when there is a difference in the fluorescence reaction) may
have different results.
11.1.4 Scanner method
Use a scanner to read the chromaticity value (Lab) of the stained cloth pieces before
and after washing. Use Formula (1) to calculate the change of chromatic aberration
Ei of the stained cloth pieces before and after washing, so as to evaluate the
detergency. Before and after washing, read the largest effective area of the center of
the front side of the cloth pieces Lab1 and Lab2.
The value of chromatic aberration (Ei) of a certain type of stain shall be calculated in
accordance with Formula (1):
L1i, a1i, b1i---the L, a and b value obtained through measurement of the ith stained cloth
piece before washing;
L2i, a2i, b2i---the L, a and b value obtained through measurement of the ith stained cloth
piece after washing.
NOTE: adopt a tablet scanner that complies with the stipulations of GB/T 18788 and
equipped with working software that reads the Lab value of the images and
calculates the chromatic aberration E. The scanner method is applicable to the
evaluation of detergency of various colored stains. For detergents added with
florescent whitening agents, the consistency between the test result by the
scanner method and that of the manual visual inspection will be reduced.
11.2 Evaluation of Whiteness Preservation
In accordance with the whiteness change of the fabric material tested for whiteness
preservation before and after washing by the sample detergent and the reference
detergent, adopt the mode similar to the evaluation of detergency (11.1) to evaluate
and calculate the whiteness preservation capability of the detergent.
Appendix A
Selection Principles, Quality Requirements and Types of Stained Cloth Pieces
Used in Detergency Test
A.1 Basic Principles for Selecting Types of Stain Used for Detergent’s
Performance Evaluation
Choose in accordance with the following modes:
a) Select stains that are representative and frequently appearing in people’s
daily lives;
b) The stain material shall be able to represent the originality of common stains
in daily life and be applicable to laboratory evaluation;
c) The dyed stain material has good discrimination, as well as good stability and
d) Select the mainstream cloth in the market as the carrier, namely, cloth base,
for the stain material preparation.
A.2 Classification of Stains
Classify stains in accordance with the following modes:
a) In accordance with the natural state of the stain source, the stains can be
divided into solid stains, liquid stains and pasty stains;
b) In accordance with the representative types of stains in life, the stains can be
divided into three types: food stains, household stains and environmental
---Food stains mainly include: tea / coffee stains, wine stains, milk stains,
edible oil stains, seasonings / sauce stains, fruits and vegetables / juice
stains, grain food stains and infant food stains, etc.
---Household stains mainly include: sebum stains, blood stains, cosmetic
stains, mineral oil stains, pen and ink stains, etc.
---Environmental stains mainly include: soot stains, soil stains and grass
stains, etc.
A.3 Requirements for Quality