February 10, 2022
When the fabric is rubbed, hairballs form. Pilling can be roughly divided into three stages, the generation of hair, the formation of hair balls and the shedding of hair balls.
Pilling of the fabric not only affects the appearance of the fabric, but also reduces the performance of the fabric.
Currently, there are four methods for testing fabrics for pilling,
Circular orbit method, Martindale method, pilling box method and random roll method.
At home and abroad, a five-level system is used to evaluate the pilling degree of fabrics. The larger the number is, the better the pilling resistance of the fabric is.
1. The purpose and requirements of the experiment
According to the following three criteria
GB/T 4802.1 "Pilling Test of Fabrics - Circular Locus Method", GB/T 4802.2 "Pilling Test of Fabrics - Martindale Method", GB/T 4802.3 "Pilling Test of Fabrics - Pilling Box Method"
The specified method, do the pilling test
This chapter learns to test the pilling performance of fabrics with a pilling tester.
Through experiments, master the basic principles and test methods of fabric pilling.
2. Experimental instruments and tools
GB/T 4802.1 JIG 040.
This instrument is used to test woolen fabrics, chemical fiber pure cotton, blended, knitted, and woven fabrics for fluffing balloons to identify product quality and process effects. During the test, the fabric was rubbed against a nylon brush and abrasive, or only in a conditioned condition with abrasive.
The contact gap between the grinding head and the grinding table plane is less than or equal to 0.2mm
Parallelism of grinding head and grinding table≤0.3mm
The relative movement path between the grinding head and the grinding table is 40±1mm
Nylon brush surface is flat, and its height difference is less than 0.5mm
The reciprocating speed of the grinding machine is 60±1 times/min
Grinding head weight 490cN±1%
Sledgehammer weight 290cN±1%
Small weight 100cN±1%
Times selection 1~9999
Meet standard testing requirements
Knitted fabrics, several pieces of machine fabrics.
Cut 3 pieces of circular chemical fiber fabrics with a diameter of 113mm and 5 pieces of wool fabrics, put the samples in the standard atmosphere and adjust the humidity for more than 16h, and then test.
4. Experimental methods and procedures
4.1 Sample making:
Five circular samples were cut from the sample, each sample having a diameter of (113±0.5) mm. The signal is marked on the back of each sample fabric. If the fabric has no obvious front and back sides, test both sides. Another comparative sample, required for evaluation, is the same size as the sample.
Use a 100c㎡ (3013mm) disc sampler to sample directly at the sampling point
Using a circular sampling template: place the circular template on the fabric to be sampled, draw a cutting line along the edge of the template, and cut the sample with scissors.
NOTE: When sampling, the sample should not include the same warp and weft yarns.
4.2 Preparation before experiment
The instrument should be placed horizontally and the nylon brushes should be kept clean. If the instrument is used daily, clean it at least once a week. Clean the brushes with a suitable solvent (eg acetone), brushing by hand to remove short lint and clips to remove protruding nylon filaments.
Place the foam plastic gasket, the sample and the abrasive on the test chuck and grinding table respectively, and the sample should face outwards.
According to the five test parameters specified in Table 1, the test parameters are selected according to the fabric type for testing.
Note 1: Other fabrics not listed in Table 1 may refer to similar fabrics described in Table 1, or select parameters according to the agreement of the relevant parties.
Note 2: All types of fabrics are not expected to test or pill when worn. Therefore, for fabrics with special structures, relevant personnel can agree on the number of pilling.
4.3 Experimental steps
Load the sample and abrasive, apply pressure to the fabric sample marked in Table 1, set the number of times, and then start the instrument to the preset number of times.
4.4 Evaluation of hairballs
The grading box should be placed in a dark room, ie a dark room.
In the middle of the sample panel of the rating box, place 1 tested sample and 1 untested control sample side by side along the fabric. Secure in place with PVC tape if needed. Test samples are placed on the left and no test samples are placed on the right. If the test specimens are preconditioned prior to the pilling test, the control specimens shall also be preconditioned specimens. When the test sample is not pretreated before the test, the comparison sample shall be the non-pretreated sample.
To ensure the objectivity and accuracy of the evaluation, pay attention to the following points:
To prevent looking directly at the light, observe the sample directly from the front of the sample at the edge of the evaluation box.
Due to the subjective nature of the assessment, multiple assessments are recommended.
Record other instances of surface changes.
Record the grade of each sample and calculate the average of the rating results. If the mean of the test results is not an integer, the nearest half-series is taken. The difference between the test result and the average shall not exceed half a grade. If more than half a grade, the number of grades per sample should be reported.
5. the requirements of the experimental report
Records: sample name and specification, instrument model, instrument operating parameters, raw data.
Assessment: Pilling progression.