Automatic Shrinkage Test Method

Test apparatus:

• Automatic shrinkage washer
• ECE non-phosphate detergent
• ICE non-phosphate detergent
• Drying oven
• Scale
• Sewing thread
• Needle
• Pen
• Fabric

Test piece preparation:

Choosing the smooth test piece, the size of it should be greater than 500mm*500mm. Or we can choose the length of the full width at least 500mm if the breath is less than 500mm. Three pairs of tags are marked along the warp and weft of the test piece, the distance between two tags should greater than 350mm, and the distance between the tag and the edge should greater than 50mm. On occasion, we can choose the test piece with 250mm*250mm, three pairs of tags are also marked along the warp and weft of the test piece, the distance between two tags is 200mm.

Test procedure:

1. Pouring the detergent into the shrinkage washer, ECE non-phosphate detergent (without fluorescent brightener) and ICE nonphosphate detergent (with fluorescent brightener) are suitable for both type A and type B shrinkage washer.
2. Putting the prepared test piece and dummy into the shrinkage washer, and selecting temperature, water-level and time and putting the prepared test piece and dummy into the shrinkage washer.
3. After that, we can make the test piece dry in one of the following manners.
4. Hang dry. We spread and hang the test piece on the laundry rack to dry it at room temperature.
5. Drip dry. We spread and hang the test piece on the laundry rack to dry it at room temperature without spin.
6. Lay flat. We flatten the test piece on the horizontal plate smoothly by hand (without any force of spread and twist).
7. Flat pressing. We flatten the test piece on the press plate, set the suitable temperature and time, and record the temperature and press.
8. Tumble dry. We can dry the test piece by cylinder dryer, and choose the low temperature for heat-sensitive fiber.
9. Oven drying. We flatten the test piece on the screen mesh of the drying oven, and set the temperature of 60±5℃ (without any force of spread and twist).

Test measurement:

1. The test piece is put on the table without any force of spread, and the shrinkage rate will be got by the ratio scale directly.
2. The shrinkage rate can also be calculated from the length of three pairs warp and weft (accurate to 1mm) by the graduated scale, and put the average into the formula.

Test formula:

DC=（B-A）/A*100%

In the equation:

DC – The rate of dimensional change

A – The size before washing

B – The size after washing