What you must know about polyester fabrics

Color fastness to abrasion and rubbing of polyester

1. Take the fabric 10cm in warp direction and 25cm in weft direction;

2. Dry grinding: Place the cut fabric flat on a dry and wet grinding machine, and adjust the number of frictions to 20 times. Take a white plain lining cloth (usually cotton woven 09 lining, thinner) 5cmX5cm size cloth, cover On the rubbed cylindrical mold, the outer ring mold is required to be slightly higher than the friction part of the inner cloth. If the outer ring mold is lower than the friction part of the inner cloth, the accuracy of the test results will be affected;

3. Wet grinding: soak the white plain cloth, and squeeze out the water between the two round pipes on the right side of the friction machine (specially used for squeezing the cloth). The other procedures are the same as dry grinding.

Polyester twist rate

Take the fabric 60cm X 60cm, the middle warp and weft are perpendicular, draw a bright line 50cm X 50cm, then stitch the two pieces together, machine wash at room temperature 40°C, 50:1 for 15 minutes, clean and iron, and measure the distortion rate; The average value of the distortion rate of 3 times is used as the calculation result)

Polyester shrinkage rate

1. Heat shrinkage: Cut the fabric into 30cm X 30cm vertically along the warp and weft, simmer for three minutes with steam, and measure its shrinkage after cooling;

2. Cold shrinkage: Take the fabric 80cm X 80cm, the middle warp and weft direction is vertical, draw an open line 50cm X 50cm, then sew it, machine wash at room temperature 40°C, 50:1 for 15 minutes, clean it and iron it, and measure its shrinkage Rate.

Polyester cloth surface appearance

1. Color difference: When inspecting the cloth surface, cut a 10cmX10cm piece of cloth from the front section, and compare the front and rear, left, middle, and right color differences when inspecting 10-20M fabrics;

2. Defects: tight yarn, broken yarn, broken spandex, marks, uneven dyeing, knots, colored yarn, interwoven yarn, stains, flying flowers, concave edges, wear marks, wrong yarns, etc. are easy to appear on the cloth surface. Outside the scope of collection, need to change the film category;

3. Weft skew: When inspecting the cloth surface, visually check whether the warp and weft directions are vertical. The weft skew detection method is: use the warp direction to be vertical, use a "T"-shaped ruler to be perpendicular to the weft direction, and start with a weft yarn extending from the left. To the right, use painted powder as a mark. After completion, the distance between the mark and the latitude ruler is the latitude value.

4. Defects: When inspecting fabrics, the four-point system is used to determine the deduction standard.

The following points should be paid attention to when using the four-point system to inspect polyester:

1. Deductions for defects are based on the principle of visibility, minor and difficult to detect defects will not be deducted;

2. Deductions for defects in the code shall not exceed 4 points, and those exceeding the points must be cut;

3. If there are false cuts, points will also be deducted according to the above standards;

4. Any type of hole that seriously affects the appearance will be deducted 4 points;

5. The inspection quantity is generally 10% of the total amount of fabrics;

6. Organization structure: (cloth mirror) the number of warp and weft yarns within 1 inch. (Thickness, tightness, weight);

7. Width: ±1cm;

8. Cloth length: The cloth length of the fabric cannot be less than the marked length;

9. Weight: square weight ±5%;

10. Calculation formula of 100 square code defect score

100% polyester standard judgment basis

The determination of the standards for discoloration, staining, dry grinding, wet grinding, color-to-color, torsion rate, and light fastness are all based on the "Grey Sample Card for Staining Evaluation" and "Gray Sample Card for Evaluating Discoloration".

1. Cut 1 meter of cloth according to the number of each cylinder and make a table of cylinder difference;

2. Cut 5cmX5cm according to each cylinder and each horse, and make a horse difference table;

3. After the above two items are done, compare the D65 light source in the color matching light box;

4. High-temperature ironing is easy to produce heat shrinkage, and the longer the ironing time, the greater the shrinkage rate;

5. After friction, it is easy to produce fluffing and pilling;

6. Dry/wet rubbing color fastness, light fastness, cold shrinkage and cloth surface effect are all better than natural fiber.