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I. Penetrating power: Weigh 4 g of the penetrant and dilute it in 100 mL of water. Take 10 mL of this solution into a beaker and add 80 mL of water. Add another 10 mL of liquid caustic (30%) (Note: Add it slowly while stirring). This solution is the additive solution of 40 g/L sodium hydroxide. In the experiments, we generally use liquid caustic soda instead of solid sodium hydroxide (as liquid caustic soda is used in dye factories during production), and the corresponding amount of liquid caustic soda is shown in the table below. Sodium hydroxide (g/L): 20, 40, 60, 80, 100, 120, 140, 160, 180. Solution volume: 100 mL – 5, 10, 15, 20, 25, 30, 35, 40, 45; Solution volume: 200 mL – 10, 20, 30, 40, 50, 60, 70, 80, 90. In these prepared solutions, canvas pieces cut to 1 cm×1 cm size were placed horizontally (standard cotton canvas: made from 3 strands of 28 denier (21 counts) and 2 strands of 28 denier 4-count fabric, cut into 1 cm×1 cm squares). The stopwatch was started immediately, and it was stopped once the canvas pieces were completely soaked; the time required for complete soaking was recorded. This test was repeated 5 times, and the average value was taken as the penetration time for the penetrant sample. II. Alkaline resistance: Weigh 4 g of the penetrant and dilute it with 100 mL of water. Take 10 mL of this solution into a beaker and add an appropriate amount of water. Different amounts of liquid caustic (30%) are then added (note: it must be added slowly while stirring) to prepare auxiliary solution of varying concentrations. Leave it for a certain period of time. Visually assess the clarity of the prepared solution. Solutions that separate into an oil layer are not tolerant to this concentration of alkali. III. Capillary effect: Weigh 4 g of the penetrant and dilute it with 100 mL of water. Take 10 mL of this solution into a beaker and add 80 mL of water. Add 1.5 mL of liquid caustic (30%) (Note: Add it slowly while stirring). Pour the prepared solution into the dyeing cup, place a cotton cloth over it to seal it, put it into the sampling machine, and treat it at 98 degrees for 45 minutes. Take it out, wash it clean, and dry it. The treated and dried cotton cloth was cut into strips measuring 5cm×20cm. A horizontal line was drawn 1 cm from one end of each strip, a weight was attached at that line, while the other end was fixed to the capillary effect tester. Immerse the cloth strip in the solution up to the horizontal line, treat it for 30 minutes, remove it, measure the height to which the solution has risen, and take the average value. The higher the height, the better the hair efficiency. IV. Whiteness: Weigh 4 g of the penetrant and dilute it with 100 mL of water. Take 10 mL of this solution into a beaker and add 80 mL of water. Add 1.5 mL of liquid caustic (30%) (Note: Add it slowly while stirring). Pour the prepared solution into the dyeing cup, place a cotton cloth over it to seal it, put it into the sampling machine, and treat it at 98 degrees for 45 minutes. Take it out, wash it clean, and dry it. A whiteness meter is used to determine the whiteness value of the treated fabric surface. V. Emulsifying power: Take 20 mL of the 0.1% additive solution and place it in a stoppered measuring cylinder, then add 20 mL of liquid paraffin (mineral oil). Cover with the stopper, shake vigorously up and down 5 times, let it rest for 1 minute, then shake vigorously up and down 5 times again and let it rest for 1 minute; repeat this process five times. Start the stopwatch timing. Record the time required to separate 10 mL of the solution. The longer it takes to separate 10 mL of water, the better. VI. Foaminess: Take 20 mL of the 0.1% additive solution and place it in a graduated cylinder with a stopper. Seal the cylinder and shake it vigorously up and down 50 times. Immediately record the height of the foam on the surface of the solution, and start a stopwatch to keep track of the time. Record the time required for the solution foam to disappear.