Color fastness tester experience by rubbing leather

Leather is a substance prone to color migration. Color migration will not only affect the inherent color of leather, but also the color of objects in contact with it, resulting in obvious product quality defects. In practice, product quality problems and business disputes caused by leather color migration are relatively common, and leather color migration is increasingly becoming the main quality indicator of leather testing.

Essentially, color migration belongs to the category of color fastness (the ability to resist external effects without changing color), but compared to color fastness to rubbing, staining, water, heat, light, etc., color Migration is a more complex process. The leather rubbing color fastness tester is a testing instrument for testing the fastness of leathertheir leather to rubbing. Qisnun Precision Electromechanical Technology Co., Ltd. is the manufacturer. Greet customers who need to inquire. In addition, based on the content of ISO 15701 standard, qisnun\'s R&D engineers tested the color migration of domestic automotive leather, furniture leather and shoe upper leather, compared and analyzed the migration degree of colors and compared it to wet rub resistance results, to analyze the correlation of the two colors. strength results.

Instruments and materials:

Polyvinyl chloride film (white), sample test frame and sweat-proof color fastness Sample racks for degree detection are consistent, in which the weight of the hammer is 4.5 kg and the size of the bottom is 11.5 cm × 6 cm. The size of the glass plate is 8cm × 5cm and the surface is flate. The oven is conventional and can control temperature (50±2)℃. Leather Rubbing Color Fastness Tester: Qisnun Precision Electromechanical Technology Co., Ltd.

The leather samples tested are divided into automotive leather, furniture leather and shoe upper leather according to their uses, with 10 pieces for each category. All samples were placed in a standard air environment for over 24 hours prior to experimentation.

Experimental method:

1. Determination of color migration of leather

There are currently ISO 15701 and ASTM D5552 standards for the detection method of color migration in leather. Among them, ISO 15701 uses polyvinyl chloride film as the colored adhesive material, while ASTM D5552 uses white cotton liner as the color bonded material, which should be soaked in distilled water before use. InBy comparison, the operation of ISO 15701 is simpler and widely adopted by tannery companies. This experimental operation adopts the standard method. The operation process is as follows:

Cut out the sample (20mm × 30mm) with a die, and then stick the tested surface of the sample on a polyvinyl chloride film (PVC for short, 50 mm × 30 mm), with the tested surface facing down Placement, place the sample centrally between two peel plates, place the plate in the apparatus, and place a 4.5 kg weight on it, rotate the device carefully while maintaining the pressure, move the weight so that the sample is in the test period Maintain an average pressure of 750 g/cm2, put the device in the oven, the temperature of the oven must be (within the range of 50±2)℃, place for 16h. Remove the sample from the apparatus and place it at room temperature to cool, then separate the sample.antillon and the PVC sheet and use the gray scale to assess the coloring of the PVC sheet.

The color sticking evaluation results are given in accordance with the requirements of GB/T 251 and are divided into 5 levels, of which level 5 indicates the absence of color sticking and color migration, and level 1 indicates heavy staining and color migration. There is a noticeable color change.

2. Determination of color fastness of leather to wet rubbing

Determination of color fastness of leather to wet rubbing is carried out in accordance with the requirements of QB/T 2537, the operation is as follows: soak in deionized water, and the white felt after the water pressing treatment is fixed on the test head (500g) of the color fastness tester by rubbing, and then the leather sample is clamped on the instrument\'s testing table, with the smooth side up and stretched 10% clockwise.friction; lay down the belt felt test head, start the instrument, stop after 250 times, remove the felt, and evaluate the color adhesion of the felt according to the requirements of GB/T 251.

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