YY/T 0681.2-2010 English PDF (YYT0681.2-2010)
YY/T 0681.2-2010 English PDF (YYT0681.2-2010)
YY/T 0681.2-2010: Test methods for sterile medical device package. Part 2: Seal strength of flexible battier materials
PHARMACEUTICAL INDUSTRY STANDARD
OF THE PEOPLE’S REPUBLIC OF CHINA
Test methods for sterile medical device package - Part 2:
Seal strength of flexible barrier materials
ISSUED ON: DECEMBER 27, 2010
IMPLEMENTED ON: JUNE 01, 2012
Issued by: China Food and Drug Administration
Table of Contents
Foreword ... 3
1 Scope ... 5
2 Normative references ... 5
3 Terms and definitions... 5
4 Significance and application ... 6
5 Interference ... 7
6 Instruments ... 7
7 Sampling ... 8
8 Aging and status conditioning ... 8
9 Procedures ... 8
10 Reports ... 10
Appendix A (Normative) Interference factors of test ... 12
Appendix B (Normative) Type of seal failure ... 14
Appendix C (Informative) Precision and bias of test methods ... 16
Appendix D (Informative) Laboratory collaborative study background, description, analysis ... 19
References ... 23
Test methods for sterile medical device package - Part 2:
Seal strength of flexible barrier materials
This Part of YY/T 0681 covers the measurement of the seal strength of flexible barrier materials.
This test can be used to test the seal, between flexible and rigid materials. Sealed samples, which comply with this test method, may come from any source, EITHER formed in the laboratory OR from commercial sources.
This test method can measure the separation force, which is required to seal the specimen, AND also identify the type of specimen failure.
Note: Appendix C and Appendix D respectively give the precision and bias of the test methods, which are specified in this standard, as well as the relevant information for their determination. 2 Normative references
The following documents are essential for the application of this document. For dated references, only the dated version applies to this document. For undated references, the latest edition (including all amendments) applies to this document.
GB/T 2918 Plastics - Standard atmospheres for conditioning and testing
3 Terms and definitions
The terms and definitions, as defined in ISO 11607-12), as well as the following terms and definitions, apply to this document.
Average seal strength
Under test conditions, the average force per unit seal width, which is required to gradually separate a flexible material from a rigid material OR from another flexible 2 The Chinese standard, which is corresponding to ISO 11607-1, is GB/T19633.1 (under revision) material.
Note: The average force is generally calculated by the testing machine, from the curve of force versus fixture movement. The curve starts from the zero force value, after the test fixture force is removed. The rise period, from the zero force value to the force value required to peel the seal, cannot be used to indicate seal strength, so this segment of the curve cannot be used to calculate the average strength. The segment, in which the specimen returns to zero after complete failure, also cannot be used to calculate the average strength. The amount of data, which is removed from both ends of the measured seal strength curve, must be the same, for all tests, so that the test results for the average seal strength are comparable (see 6.1 and 9.8.1).
Indicates a material whose flexural strength and thickness allow it to be rotated 180°. 3.3
Maximum seal strength
Under test conditions, the maximum force per unit seal width, which is required to gradually separate a flexible material from a rigid material OR from another flexible material.
4 Significance and application
4.1 Seal strength is a quantitative measure, which is used for process validation, process control, process capability. Seal strength is not only used to evaluate peel force and package completeness; it can also be used to measure the ability of the packaging process to form a stable seal. The sealing strength of the package shall meet its lower limit requirements, but for ease of opening, it is often desirable to give an upper limit to the seal strength.
The maximum sealing force is important information. However, in some applications, the average force to open the seal may be specified, in which case it shall also be reported.
4.2 When adhesive failure (peeling) occurs on the sealing surface, report the measured adhesive strength value. Cohesive failure, delamination, or damage elsewhere, in the bond of the specimen, indicates the failure of the substrate, rather than the sealing interface, is a factor limiting the strength of the package. When these conditions occur, the seal strength may be reported as "not less than" the measured strength. 4.3 When testing materials, part of the measured force value may be formed by the 6.2 Sample cutter
Cut the sample into widths of 15 mm, 25 mm or 25.4 mm, the tolerance shall be ±0.5%. Note: 15 mm specimen width is preferred. If it is necessary to compare with foreign methods and data, it may also use a test width of 25.4 mm (1 in).
7.1 The number of samples shall be selected, so that the measurement is representative. 7.2 The use of test samples, which have appearance defects or other deviations from normal, may or may not be appropriate, depending on the situation; it is determined by the purpose of the study. Removing flaws without thinking can bias results. 8 Aging and status conditioning
8.1 When there is no information to show that, the heat-sealing strength of the tested material can be stabilized in a relatively short period of time, carry out the status conditioning and test, for the sealed material, according to GB/T 2918. The shortest state conditioning time is 40 h. If it is shown that it takes longer time to achieve stability, then a longer state conditioning time is required.
8.2 The state conditioning time of heat sealing can be shortened by testing, provided that the sealing strength can be stabilized.
8.3 In order to meet specific test purposes, such as measuring seal strength at specified storage or transport temperatures, it may be necessary to modify the status conditioning process.
9.1 Calibrate the tensile testing machine, as recommended by the manufacturer. 9.2 Cut the seal specimens to the dimensions, as shown in Figure 2. The edges of the sample shall be neat and perpendicular to the sealing direction; the wings may be shorter than those shown, depending on the size of the tester's fixtures.
a) Complete identification of the test material;
b) The equipment, test methods or procedures used to form the seal, if known; c) The equipment used for the test seal;
d) Test environmental conditions: Temperature and humidity;
e) Fixture moving speed;
f) Initial spacing of fixtures;
g) Sealing width;
h) The relationship between the machine direction of the material and the stretching direction;
i) The force (strength) value to achieve effective failure;
j) The method of holding the tail AND the special holder for holding the specimen; k) If the seal is formed between two different materials, record the material which is held by each fixture;
l) Number of samples to be tested AND sampling method;
m) Any other relevant information, that may affect the results;
n) The type of sample failure, which is determined by visual inspection, in accordance with Appendix B;
o) The maximum force, to which each specimen is stretched to failure. Preferably expressed in Newtons/meter (N/m) or Newtons/original specimen width (mm); Note: YY 0698.4 and YY 0469.5 standards require N/15 mm as the unit. Although this kind of representation is not standardized, it is a relatively common representation method in the world.
p) Average peel force, if applicable (see 9.8);
Note: If reporting this measurement, there should be a description of the algorithm used to calculate the mean.
q) Plot the force corresponding to the movement of the fixture, if necessary; r) Other data not affected by interference, if these data are for specific test purposes; s) Any statistical calculations deemed appropriate (mean, range, standard deviation is most commonly used).
Interference factors of test
A.1 Types of failure
A.1.1 The purpose of this test method is to measure the sealing strength of flexible barrier materials. The strength of the seal is determined, by measuring the force required to peel off the seal, when a tensile force is applied to both ends of the sealed material sample. However, this stretching process may or may not result in the desired type of specimen failure. During a test cycle, the specimen is separated at a set speed, AND the force on the end of the specimen is continuously measured. Tension at both ends of the specimen can cause one or more of the following to occur in the specimen: - Separation (peeling) of sealing surfaces;
- Material breakage or tearing at the sealing edge;
- Failure of the substrate beneath the seal;
- Material delamination;
- Material elongation;
- Material breaks or tears away from the seal.
Only the first case (and sometimes the second case) is reported, as a direct result of seal strength. The other four cases must be identified in the test report, because the material itself fails. In this test, the sample fails at the weakest points; since these points may not be at the seal, other modes of failure appear, which interfere with the test AND prevent the method from measuring real seal strength.
A.1.2 Sealing characteristics, such as deformation, shrinkage, burn through, will affect the test results.
A.2 Effect of material elongation on peeling speed
Elongation of the material, during the test, is another interference. If the specimen is elongated, during fixture movement, the actual peel speed will be lower than the calculated peel speed, which uses the speed of the fixture movement. In this case, the elongation-to-peel ratio is unknown AND may vary during the test, so that the peel speed is no longer under machine control. Peel speed is a factor, which is known to affect the measured seal strength.
Precision and bias of test methods
C.1.1 ASTM uses ASTM E691 as a guide, to carry out a laboratory collaborative study on this test method 3). In 18 laboratories, the 1980 (10 samples x 18 laboratories x 11 techniques) samples are measured in 3 different test groups (6 laboratories each). In order to focus on the test method itself, laboratory samples are used with little seal variation. A description of the measurement materials and methods used are listed in Table C.1. The 7 different brands of tensile testing machines are used to collect data. Table C.2 lists the model and sensor size of the testing machine. Table C.3 lists the repeatability and reproducibility conclusions. Figure C.1 is a graphical representation of the data.
C.1.2 Concepts of "r" and "R" in Tables C.3 and C.4
If the repeatability standard deviation (Sr) and reproducibility standard deviation (SR) have been calculated, from sufficiently large parental data, meanwhile the test results are the mean of the results of 10 ~ 30 samples (see Note 1) per test, then the following is applicable:
Note: The Appendix of this standard gives the repeatability and reproducibility comparison of smaller sample size (n = 10).
C.1.2.1 The repeatability limit "r" is the interval describing the critical range, between test results, which are measured by the same operator, on the same day, using the same equipment, by the same method, for the same material. If the test results differ by more than the "r" value of the material or method, they shall be considered non-equivalent. C.1.2.2 The reproducibility limit "R" is used to describe the interval of the critical range, between test results, which are obtained by the same method, on the same material, by different operators, using different equipment, not necessarily on the same day. If the test results differ by more than the "R" value of the material or method, they shall be considered non-equivalent.
C.1.3 The correct probability of judgment according to C.1.2.1 or C.1.2.2 is 95% (0.95). 3 The test method of ASTM F88-06 corresponding to this standard.
Laboratory collaborative study background, description, analysis
D.1 In order to form the statement of precision and bias in Appendix C, a laboratory collaborative study was conducted in 18 laboratories, in 2004 4). Two subcommittees, ASTM F02.3 and F02.6, jointly participated in the verification of nearly 2000 samples, using a tensile testing machine, that met the requirements described in the instrumentation chapter of this standard. Since the methods and techniques, which are discussed in this standard, are the focus of the study, the Joint Committee has drawn up that the sample shall be as homogeneous as possible. That is, samples are not prepared by production machines, BUT by controlled laboratories. Therefore, samples are taken from one production batch from each of the three voluntary sample preparation companies; uniformly sealed by a laboratory sealing machine; cut into prescribed sizes; then sent to each laboratory and its designated contact person.
D.1.1 A total of 3 schemes are designed, each with a different combination of materials. Materials used include the seal which is formed by the heat seal adhesive paper and film (PET/LDPE), the seal which is formed by the uncoated Tyvek 1073 B material and film (PET/LDPE), a face-to-face seal which is formed by a material group with peelable sealant (3 mil film/film and 5 mil film/film). Each series of samples is designed to identify the effect of the test method used, on the final measurement results and the variability of repeatability (r) and reproducibility (R). These techniques are listed in Table D.1.
D.1.2 The laboratory collaborative study is basically carried out separately. If the measured values or the techniques, that affect the r and R values, are not fixed, the data between groups will not be comparable, so that it can observe the impacts of the material type and anomalous lab resources.
D.1.3 A decision, which is made by the Joint Committee, is to ensure the required sample size for effective measurement (take n = 30 and n = 10). It is agreed that, in order to obtain reliable data from established test methods, a larger sample size must be used, so that a description of variability with statistical significance can be obtained. For all laboratories to test all materials and techniques, the sample size required is very large (30 samples x 18 laboratories x 11 techniques). To reduce the number of tests, the laboratory collaborative studies are divided into 3 independent series groups as shown in Table D.1. In order to solve the problem of accuracy and confidence in the results of the analysis, the data were divided into two data groups of n = 30 and n = 10; the latter takes the first 10 data, which is reported by each laboratory. The results of the study are 4 Appendix D is the test in ASTM F88-06.