GB/T 16585-1996Rubber, vulcanized. Test method of resistance to artificial weathering (Fluorescent UV lamp) (English PDF)

4.4 Blackboard thermometer

The blackboard thermometer is composed of a black aluminum plate of

75mm×10mm×2.5 mm connected with a temperature sensor. It shall be in the range of the exposure center so that it reflects the test temperature as much as possible.

4.5 Instruments and reference materials for measuring radiation

According to conditions and needs, a radiation meter or reference materials may be used to measure the light energy received by the sample.

4.5.1 Radiation meter

Radiation meter includes integrated illuminance meter and radiometer.

4.5.2 Reference materials

The blue wool standard shall comply with the relevant provisions of GB 730; the standard gray scale shall comply with the relevant provisions of GB 250.

6.5 During the condensation exposure period, the equilibrium temperature of the hot

water in the selected water tank shall be kept within ±3°C.

6.6 The water supplied to the water tank may be distilled water, deionized water or potable tap water.

6.7 The closest distance between the specimen surface and the lamp plane is 50mm and parallel.

6.8 The irradiance in the wavelength range of 280~400nm received by the surface of the specimen is usually no more than 50W/m2, and there shall be no radiation below

270nm.

6.9 In order to facilitate inspection and termination of the test, the exposure test time is generally specified as a multiple of 24h, 7d or a multiple of 7d.

7.1 Specimen installation

The specimen is mounted on the specimen holder in a free state, with the exposed surface of the specimen facing the lamp. When the specimen is not filled with the holder, fill the remaining space with blank plates to keep the test conditions in the chamber stable. During the exposure period, the position of the specimen in the center of the exposed area and the edge of the exposed area shall be changed regularly to reduce uneven exposure.

7.2 Exposure test

Start the test chamber, adjust the specified test conditions; and record the exposure starting time; and keep the specified test conditions constant throughout the exposure period.

7.3 Determination of UV radiation

7.3.1 Measuring radiation dose by instrument

Regularly place an ultraviolet light integrated illuminometer or radiometer on the side of the exposed specimen holder to directly measure the received ultraviolet radiation dose.

Appendix A (Standard)

Use Method of Measuring the Light Radiation Dose by the Blue

Wool Standard

A.1 Instruction

Blue wool standard fabric sample (referred to as "standard sample") is used to assess the grade of color fastness to light and weathering of colored textiles. Because the blue dye is sensitive to light radiation and has a certain quantitative relationship, it may be used to determine the radiation dose level, that is, the exposure period. The blue wool standard sample is divided into eight grades (that is, 8 numbers), which represent 8 light fastness grades. Because the standard sample is easy to use and has a lot of data based on its use, it may be used to determine the exposure period of the rubber light-resistance exposure test.

NOTE: Refer to GB 730 for details.

A.2 Procedure

A.2.1 A set of blue wool standard samples numbered from 1 to 8 (level) are placed adjacent to the specimen and the exposure test is carried out at the same time.

A.2.2 Compare the color difference between the exposed blue wool standard sample

and the unexposed blue wool standard sample, and compare it with the color difference level of the "grey scale for assessing discoloration". When the color difference of the No. 1 standard sample reaches the color difference of Level-4 of the gray scale, then the radiation dose level (exposure level) is 1/1, that is, the exposure period is 1/1. When the color difference of the No. 2 standard sample reaches the same color difference of Level-4, that is, the exposure period 2/1 level; and so on, until the No. 8 standard sample shows the color difference of Level-4, that is, the exposure period 8/1 level.

A.2.3 When the first batch of 8 standard samples reach level 8/1, replace with the second batch of newly prepared No.1~No.8 standard samples; and continue to expose them until the second batch of 8 standard samples show the color difference with the unexposed 8 standard samples to be color difference of Level-4 of gray scale, that is, the exposure period 8/2 level.

A.2.4 Discard the second batch of 8 standard samples and replace them with the third batch of newly prepared No.1~No.8 standard samples to continue exposure. When the third batch of 8 standard samples reaches color difference of Level-4, that is, the

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