EN71Various sample pretreatment methods

1Selection of testing section

The laboratory samples for testing must be toys in sales or available for sale status.The testing part must be removed from the accessible part of a separate toy sample, which means,The same material on the toy can be combined as a separate testing part, but other toy samples cannot be used.The testing section is not allowed to contain more than one material or color, unless physical separation methods cannot form separated samples,This type of sample, such as dot dyed, printed textiles, or due to limited weight.

（note:This requirement does not exclude the testing portion that can be removed from materials that represent the above-mentioned regulations and their attached substrate materials）

Insufficient materials10mgThe testing part will not be tested.

2Paint,varnish,Nitro lacquer,ink,Polymer coatings and similar coatings

The coating should be obtained from the sample at room temperature using mechanical methods, and the sample should not be crushed beyond the ambient temperature. From the aperture to0.5mmObtained from the material of the metal sieve0.2gThe testing section. If the same coating after crushing can only be obtained10mgto100mg,It must be distinguished from0.2gThe sample must be tested, and the content of relevant elements must be determined according to the testing section used100mgCalculate the time and list the quality of the testing section in the report.

When the coating cannot be crushed due to its properties（Like elasticity/Plastic paint）Remove the test portion from the sample without crushing the coating. Use containers of appropriate size（25mlCone shaped bottle), will10mlThe temperature is（37±2）℃ hydrochloric acid solutionC=0.07mol/LMixed with testing section.If the quality of the testing section10mgand100mgBetween them, use the above solution5.0mlAt a temperature of（37±2）Mix with the testing section at ℃. shake1Minutes, then check the acidity of the mixture. ifPHValue greater than1.5While shaking the mixture, add hydrochloric acid dropwiseC=2.0mol/LThe aqueous solution untilPHreach, achieve, attain1.0to1.5Between them, keep the mixture away from light at a temperature of（37±2）Stir the mixture at ℃ for one hour, then let the mixture（37±2）Place at ℃ for one hour. Immediately separate the solid matter from the mixture, first filter it through a membrane filter, and then centrifuge as needed (if there is still turbidity present after filtration) until the acceleration reaches5000g（g=9.80665m/s）Centrifugal separation. Separation must be carried out as soon as possible after the above-mentioned storage time has ended, and centrifugal separation cannot exceed10Minutes, and the use of centrifugal separation must be noted in the report.

If the prepared solution needs to be stored for more than one working day before analysis, hydrochloric acid must be added to stabilize it,Make the concentration of the stored solution approximatelyC=1mol/L.

3Polymer materials and similar materials,Including laminated materials reinforced with or without textiles,But not including others

textile

Remove from polymer materials or similar materials0.2gIn the testing section, pay attention to preventing the material from being heated,The specific method is as follows:

Cut the test section from the small thickness of the material cross-section,In order to maximize the ratio of the surface area of the specimen to the mass of the specimen, all dimensions of each specimen must be less than or equal to when not under compression6mmUse containers of appropriate size（25mlErlenmeyer flask）, will10mlThe temperature is（37±2）℃ hydrochloric acid solutionC=0.07mol/LMixed with the testing section. If the quality of the testing section is10mgand100mgBetween them, use the above solution5.0mlAt a temperature of（37±2）Mix with the testing section at ℃. shake 1 Minutes, then check the acidity of the mixture. ifPHValue greater than1.5While shaking the mixture, add hydrochloric acid dropwiseC=2.0mol/LThe aqueous solution untilPHreach, achieve, attain1.0to1.5Between them, keep the mixture away from light at a temperature of（37±2）Stir the mixture at ℃ for one hour, then let the mixture（37±2）Place at ℃ for one hour.

Immediately separate the solid substances from the mixture effectively,First, use a membrane filter to filter,Then, as needed（If there is still turbidity after filtration, centrifugal separation is required）When the acceleration reaches 5000g（g=9.80665m/s）Centrifugal separation. Separation must be carried out as soon as possible after the above-mentioned storage time has ended, and centrifugal separation cannot exceed 10 Minutes, and the use of centrifugal separation must be noted in the report.

If the prepared solution needs to be stored for more than one working day before analysis,It is necessary to add hydrochloric acid for stabilization, so that the concentration of the stored solution is aboutC=1mol/L.

4Textile fabrics

Cut off the test section from the material, and all dimensions of each specimen must be less than or equal to when not under compression6mmUse containers of appropriate size（25mlErlenmeyer flask）, will10mlThe temperature is（37±2）℃ hydrochloric acid solutionC=0.07mol/LMixed with testing section.If the quality of the testing section is10mgand100mgBetween them, use the above solution5.0mlAt a temperature of（37±2）Mix with the testing section at ℃. shake 1 Minutes, then check the acidity of the mixture. ifPHValue greater than1.5While shaking the mixture, add hydrochloric acid dropwiseC=2.0mol/LThe aqueous solution untilPHreach, achieve, attain1.0to1.5Between them, keep the mixture away from light at a temperature of（37±2）Stir the mixture at ℃ for one hour, then let the mixture（37±2）Place at ℃ for one hour. Immediately separate the solid matter from the mixture, filter it through a membrane filter, and then proceed as needed（If there is still turbidity after filtration, centrifugal separation is required）At an acceleration of5000g（g=9.80665m/s）Centrifugal separation. Separation must be carried out as soon as possible after the above-mentioned storage time has ended, and centrifugal separation cannot exceed 10 Minutes, and the use of centrifugal separation must be noted in the report.

If the prepared solution needs to be stored for more than one working day before analysis, hydrochloric acid must be added to stabilize it, so that the concentration of the stored solution is aboutC=1mol/L.

5Paper and cardboard

Cut the paper and cardboard as small as possible and weigh them0.2gFirst, join in5mlSoak the sample in distilled water to form a uniform mixture, and then add5mlThe temperature is（37±2）℃'s0.14mol/LHydrochloric acid, check acidity（PHfor1-1.5Between). In a constant temperature shaking water bath, stir in the dark for one hour, then let it sit for another hour, and immediately separate the solid substances in the mixture effectively. First, use a filter membrane to filter, and then, as needed（If there is still turbidity after filtration, centrifugal separation is required）When the acceleration reaches 5000g（g=9.80665m/s）Centrifugal separation. Separation must be carried out as soon as possible after the above-mentioned storage time has ended, and centrifugal separation cannot exceed 10 Minutes, and the use of centrifugal separation must be noted in the report.

If the prepared solution needs to be stored for more than one working day before analysis,Hydrochloric acid must be added to stabilize it,Make the concentration of the stored solution approximatelyC=1mol/L.

6Metal, glass, ceramic materials

First, conduct small part testing on toys and toy components. If the toys or toy components are fully contained in the small part tester and contain touchable metal/glass/Ceramic materials, if coated, should first remove the coating from the toy or toy component, and then place the toy or toy component inside50mlGlass container:60mm,diameter40mmAdd sufficient temperature to37±2℃'sC=0.07mol/LA hydrochloric acid solution is used to ensure that the solution can properly immerse toys or toy parts. The container is covered to prevent the contents from being exposed to light37±2Place at ℃ for two hours. Immediately separate the solid matter from the mixture and filter it through a membrane filter.

7Materials that can leave traces

If the material solidifies under normal conditions and contains grease,oil,Wax or similar materials must be allowed to solidify under normal conditions in the test section, and then the solidified material must be wrapped in hard filter paper. The above components must be removed by dissolution extraction using n-heptane solvent,The analytical method used must ensure that the removal of the above components is quantitative.

1）Remove the sample without oil, grease, wax or similar materials0.2g, will10mlThe temperature is（37±2）℃ hydrochloric acid solutionC=0.07mol/LMixed with the testing section. If the quality of the testing section is10mgand100mgBetween them, use the above solution5.0mlAt a temperature of（37±2）Mix with the testing section at ℃. shake1Minutes, then check the acidity of the mixture. ifPHValue greater than1.5Shake the mixture while shaking it,Add hydrochloric acid dropwise on one sideC=2.0mol/LThe aqueous solution untilPHreach, achieve, attain 1.0 to 1.5 Between them, keep the mixture away from light,At a temperature of（37±2）Stir the mixture at ℃,Continue for one hour, then let the mixture（37±2）Place at ℃ for one hour. Immediately separate the solid substances from the mixture effectively,First, use a membrane filter to filter,Then, as needed, reach the desired acceleration level5000g（g=9.80665m/s）Centrifugal separation. Separation must be carried out as soon as possible after the above-mentioned storage time has ended, and centrifugal separation cannot exceed10minute,The use of centrifugal separation must be noted in the report. If testing alkaline materials containing a large amount of basic calcium carbonate,Use hydrochloric acidC=6mol/LTranslate into EnglishPHAdjust the value to1-1.5To avoid excessive dilution between them,If the alkaline material is not large, use2mol/LHydrochloric acid. If the prepared solution needs to be stored for more than one working day before analysis, hydrochloric acid must be added to stabilize it, so that the concentration of the stored solution is aboutC=1mol/L.

2）For samples containing oil, grease, wax, or similar materials, leave the test sample on a hard filter paper and use an equivalent weight to the test sample25The double temperature is37±2℃Soak the test sample in water to obtain a uniform mixture. Transfer the mixture quantitatively to a suitable container. Add an equivalent mass of the original test sample to the mixture25The temperature is37±2℃ofC=0.14mol/LThe hydrochloric acid solution. Shake for one minute and check the acidity of the mixture. IfPHgreater than1.5Shake the mixture while adding dropwise2mol/LHydrochloric acid untilPHIn1-1.5Between, avoid light, at a temperature of37±2℃Stir for an hour, then37±2℃Let it sit for an hour.

Immediately separate the solid substances from the mixture effectively,First, use a membrane filter to filter, and then adjust the acceleration as needed5000g（g=9.80665m/s）Centrifugal separation. Separation must be carried out as soon as possible after the above-mentioned storage time has ended, and centrifugal separation cannot exceed10Minutes, and the use of centrifugal separation must be noted in the report. If testing alkaline materials containing a large amount of basic calcium carbonate, use hydrochloric acidC=6mol/LTranslate into EnglishPHAdjust the value to1-1.5To avoid excessive dilution, if the alkaline material is not large,use2mol/LHydrochloric acid.

If the prepared solution needs to be stored for more than one working day before analysis,It is necessary to add hydrochloric acid for stabilization, so that the concentration of the stored solution is aboutC=1mol/L.

8Flexible modeling materials（Including modeling clay）And gel

If the material contains oil or grease,Wax or similar materials must be wrapped in hard filter paper for testing, and the above components must be removed by dissolution extraction using n-hexane solvent. The analytical method used must ensure that the removal of the above components is quantitative.

1）Remove the sample without oil, grease, wax or similar materials0.2g, will10mlThe temperature is（37±2）℃ hydrochloric acid solutionC=0.07mol/LMixed with testing section.If the quality of the testing section is10mgand100mgBetween them, use the above solution5.0mlAt a temperature of（37±2）Mixing with the testing section at ℃.shake1minute,Then check the acidity of the mixture.ifPHValue greater than1.5While shaking the mixture, add hydrochloric acid dropwiseC=2.0mol/LThe aqueous solution untilPHreach, achieve, attain 1.0 to 1.5 Between them, keep the mixture away from light at a temperature of（37±2）Stir the mixture at ℃ for one hour, then let the mixture（37±2）Place at ℃ for one hour. Immediately separate the solid matter from the mixture, filter it through a membrane filter, and then accelerate it as needed5000g（g=9.80665m/s）Centrifugal separation. Separation must be carried out as soon as possible after the above-mentioned storage time has ended, and centrifugal separation cannot exceed10Minutes, and the use of centrifugal separation must be noted in the report. If testing alkaline materials containing a large amount of basic calcium carbonate, use hydrochloric acidC=6mol/LTranslate into EnglishPHAdjust the value to1-1.5To avoid excessive dilution between them,If the alkaline material is not large, use2mol/LHydrochloric acid. If the prepared solution needs to be stored for more than one working day before analysis,Hydrochloric acid must be added to stabilize it,Make the concentration of the stored solution aboutC=1mol/L.

2）For samples containing oil, grease, wax, or similar materials, leave the test sample on a hard filter paper and use an equivalent weight to the test sample25The double temperature is37±2℃Soak the test sample in water to obtain a uniform mixture. Transfer the mixture quantitatively to a suitable container. Add an equivalent mass of the original test sample to the mixture25The temperature is37±2℃ofC=0.14mol/LThe hydrochloric acid solution. Shake for one minute and check the acidity of the mixture. IfPHgreater than1.5Shake the mixture while adding dropwise2mol/LHydrochloric acid untilPHIn1-1.5Between, avoid light, at a temperature of37±2℃Stir for an hour, then37±2℃Let it sit for an hour. Immediately separate the solid substances from the mixture effectively,First, use a membrane filter to filter,Then, as needed, reach the desired acceleration level5000g（g=9.80665m/s）Centrifugal separation.Separation must be carried out as soon as possible after the above-mentioned storage time has ended,Centrifugal separation cannot exceed10minute,At the same time, centrifugal separation must be noted in the report. If testing alkaline materials containing a large amount of basic calcium carbonate,Use hydrochloric acidC=6mol/LTranslate into EnglishPHAdjust the value to1-1.5To avoid excessive dilution between them,If the alkaline material is not large,use2mol/LHydrochloric acid.

If the prepared solution needs to be stored for more than one working day before analysis,It is necessary to add hydrochloric acid for stabilization, so that the concentration of the stored solution is aboutC=1mol/L.