一、Gb24264-2009 - adhesive for finishing stone materials

        This standard specifies the terms and definitions, classifications, codes and markings, general requirements, test methods, inspection rules, and marking, packaging, transportation and storage of adhesives used in the production and installation of finished stone products.

二、GB/T 29059-2012- ultra-thin stone composite board

      This standard stimulates the ultra-thin stone composite board (hereinafter referred to as the composite board) the definition, classification, technical requirements, test methods, inspection rule, marks, packaging, transport Gu and storage, etc.This standard is applicable to ultra-thin stone composite boards for building decoration.

三、 GB 18583-2008- limits of harmful substances in adhesives for interior building decoration materials

        This standard specifies the limits and test methods of harmful substances in adhesives used for interior building decoration.This standard is applicable to adhesives for interior building decoration.

四、The ROHS standard

        RoHS standard edit RoHS is the restrictions on the use of certain hazardous substances in electrical and electronic equipment directive (the Restriction ofthe use of certain hazardous substances in electrical and electronic equipment) of the English abbreviations.Related products to professional lab for testing, to product into single material both homogenous material after testing, including lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyls (PBB) and polybrominated diphenyl ethers (PBDE) of six kinds of harmful substances conformed to the RoHS directive requirements, can be obtained if the accord with RoHS report and qualified certificate, if does not conform to, have to find another qualified products to replace.

五、LD50 [median lethal dose]

       LD50 [lethal dose of half] is the most important parameter for evaluating the acute toxicity of chemical substances, and also the basic standard for grading acute toxicity of different chemical substances.The greater the acute toxicity of the chemical, the smaller the LD50 value.It is often combined with ED50 [semi-maximum effect concentration] to calculate the therapeutic index LD50/ED50 to evaluate the safety of drugs. Drugs with large therapeutic index are relatively safe.LD50 the bigger the better, that is, high concentration should be killed half ED50 is as small as possible, means more than a few doses will be able to work alone is meaningless, one big LD50 ED50 also big, is also a big risk so described in the ratio of drug safety, and separate the LD50 can only describe the toxicity.

 

1、Yellowing resistance test:

      Weigh AB adhesive in proportion, stir it for 3 minutes until it is well mixed, then pour it into the mold after vacuumization, and let it solidify at room temperature for 7 days.Then, the specimen was placed into the ultraviolet aging box pt-2030a at 70℃ and removed from the oven after 8h. The gray card rating was compared (iso105-a02:1993).

Determine the product test level.

2、 Heat resistance to old age:

      The prepared specimens were cured for 14 days under standard test conditions, and then put into the (70±2)℃ air-blast oven for 14 days.Take them out of the oven, stick the drawing joint to the stone substrate with suitable high-strength adhesive, continue to maintain the specimen under standard test conditions for 24h, and measure the tensile bond strength.

3、Applicable test method:

      Pour appropriate amount of sample into 100ml beaker and add regular amount of curing agent to make 50g mixture. Take the sample with curing agent as the starting time, and then place the beaker in a constant temperature water bath at (23±1)℃, and make the sample surface about 2cm below the liquid level.Continuously observe the sample and read the time when the sample produces anomalies. The applicable period is from the initial time to the time when the sample produces anomalies.The sample is abnormal, refers to the apparent viscosity rise, gelation, precipitation, separation, discoloration, etc.The same sample was measured twice, and its average value was calculated, expressed as min.

4、 Pressure shear test method and data of immersion, heat treatment and freezing cycle:

        1）、 Under standard test conditions, 10 specimens were maintained for 7 days, and then entered into water of (23±2) ℃ for 7 days. The specimens were taken out, dried with cloth, and the bond strength of press-shear was measured.

       2）、 Under standard test conditions, 10 specimens were maintained for 7 days, and then put into (80±2)℃ bellows for 7 days.Air should circulate freely around each time.The specimen was taken out and placed under standard conditions for 24h to test the compressive shear bond strength.

       3）、Before the stone substrate is placed, apply 1min adhesive on its back with spatula.The specimens were cured for 7 days under standard test conditions, and then cured for 21 days in water at (23±2) ℃.Samples were taken out of water for freeze-thaw test.Each freeze-thaw cycle is:     
       a：The specimen was removed from the water and placed in a low temperature box at (-20±3) ℃ for 4h±20min

       b： The specimen was taken out of the cryogenic chamber and immersed in (23±2) ℃ water for 4h±20min

       Repeat 50 times.After the last cycle, the specimen was taken out, maintained under standard test conditions, and the drawing joint was glued to the stone substrate with suitable high-strength adhesive.The specimens were maintained under standard test conditions for 24h to determine tensile bond strength.

 

         Because stone material has natural crevices, pores and tiny holes, it is easy to absorb the erosion of the outside world.Reason this, use this one principle, add special mix color agent in glue, besmear is brush on stone material, glue and mix color agent synchrony infiltration stone material goes, glue after solidify mix color agent to also solidify inside stone material likewise, achieve deepened goal ground.