1. Purpose and Scope

1.1 This test method determines the drying rate of fabrics. While in contact with a heating plate set at 37°C, the surface temperature of the human skin increases and the body begins to sweat.

1.2 This method is applicable to all types of fabrics worn by everyone, including knitted, woven fabrics, and nonwovens, as well as fabrics derived from the final product.

2.Principle

2.1 This method determines the evaporation rate of a specified amount of water from the dry fabric at the heated metal junction when maintaining a constant temperature state.

3.Use and Restrictions

3.1 This test is conducted under controlled laboratory temperature and relative temperature and humidity conditions. Although testing can be performed under other conditions, in order to compare results, the same conditions must be used.

3.2 This test uses the same water for measurement. If water reaches the edges of the sample, then it will be necessary to increase the specimen size and repeat the test with a new specimen. Further, when comparing results, the test must be performed with the same amount of water.

3.3 The drying speed of the fabric can be tested for the membrane in its structure, as long as it is moisturized using this method. The air permeability of the fabric is greater than 5,000 g/m2/day, and water evaporation is detected. Multi-layer composite fabrics can also be tested using this method. .

3.4 When testing fabric in a sock, the sock should be opened and a portion of the sock inside come into contact with the heating plate, simulating contact between the fabric and human skin.

4.Instruments and materials

4.1 Drying rate test device.

4.2 Temperature recorder - has the function of reading data every 1 second, storing it, and transferring it to a computer data file.

4.3 Infrared thermocouple probe - temperature range 15-50±0.1°C.

4.4 Fan Box - Yields 1.5±0.5m/s air flow over heated width plate, measured directly behind the IR thermocouple probe.

4.5 Metal plate - 30.5×30.5±0.5 cm. 6.6 Flexible heater - 30.5×30.5±12.5px with controller to maintain temperature 37±1℃.

4.6 Cork board insulation - 30.5 x 30.5 ± 0.5 cm.

4.7 Micropipette, adjustable volume, 0.100-1.000±0.003 mL.

4.8 Anemometer - hot wire type, capable of measuring air flow from 0.5-2.5±0.1 meters/second.

4.9 Magnetic, plastic or metal strips, 15.0 cm long, 4.0 ± 2.0 cm wide and 0.2 ± 0.1 cm thick, can be used to hold the specimen in place.

4.10 Deionized or distilled water.

5. Sampling

5.1 Take a volume sample representative of the lot. If testing fabrics in the final product, take photos of three items from each batch.

6.Test sample

6.1 Cut three specimens (15.0 × 15.0 ± 0.5 cm) from each fabric sample from the right, middle and left positions across the width of the sample for each test.

6.2 If testing a garment or final product, take specimens from different parts of the garment; i.e. sleeves, back and front.

6.3 If testing socks or socks, cut the specimen lengthwise and test each unique structure.

7.Adjustment

7.1 Prior to testing, condition test specimens in accordance with the instructions of ASTM D 1776, Standard Practice for Conditioning and Conditioning of Textiles (see 14.2). Condition samples in the atmosphere for at least 4 hours at 21±1°C (70±2°F), 65±2% RH, laying each sample individually on a screen or perforated rack in an air-conditioned rack.

7.2 Carry out all tests in a standard atmosphere for testing purposes.

8.Procedure

8.1 Turn on the temperature controller as a flexible heater and fan, and the temperature of the metal plate is stable at 37±1°C.

8.2 Use a hot-wire anemometer to verify that the airflow on the board is 1.5 ± 0.5 meters/second. Measure airflow directly behind the infrared thermocouple probe.

8.3 Place the sample on the metal and let it stand for 5 minutes until it reaches the temperature of the metal plate. Place one side of the specimen next to the skin against the metal plate surface. Use a peel to secure the top edge of the specimen to the metal plate surface closest to the fan.

8.4 Place the infrared thermocouple probe 1.0 ± 0.1 cm above the center of the specimen. It helps to have a mark on the metal plate to center the IR field of view for the thermocouple probe.

8.5 Start the video recorder, lift the free end of the specimen (opposite side to the magnetic strip) and apply 0.200 ± 0.003 to the plate below the specimen with a ml of water probed directly under the infrared thermocouple. Reposition the specimen so that it covers the water droplet. The start time is the time when the specimen is exposed to water.

8.6 View the sample to determine the wicking profile produced by the water. Make sure water is not absorbed around the edges of the specimen. If it is water then wick to the edge of the sample use a larger sample or reduce the volume.

8.7 Collect and record the temperature every second until the temperature returns to the initial temperature. Repeat the test on additional specimens.

9. Calculation and evaluation

10.Report

11. Accuracy and bias

The above information is compiled from the Internet and is for reference and learning only.

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