Test Methods and Finishing Methods of Fabric Pilling

Fabric pilling can seriously affect the appearance of clothing, reduce wearability and even lose its value, so it is important to test pilling of fabrics. Before discussing how to test fabrics for pilling, let’s first look at how fabric pilling is formed. This will help us to understand the testing process.

What is fabric pilling?

Pilling refers to textiles or clothing in the process of washing or use, constantly subjected to rubbing and friction and other external forces, the surface of the fabric fibres protrude, the fibre end sticks out to form a pile.

When the height and density of the pile reach a certain amount, and then further friction, the pile out of the surface of the fibres entangled with each other, in the fabric surface to form a tight and opaque ball. This is the pilling process of the fabric.

The pilling test is performed by placing the specimen on a pilling tester and using a gentle friction method to pill a certain number of times and then evaluating it. There are three general methods of testing fabric pilling, namely the Martindale method, the circular locus method and the pilling box method. Different pilling methods will get different results. Want to know there comparisons? Now you can go to this article. Comparisons and Evaluation of Test Methods for Fuzzing and Pilling Resistance

Three test methods for fabric pilling

1 Martindale test method for testing the fabric pilling

Test principle: A circular test specimen is passed over a friction surface comprising the same fabric or, when relevant, a wool abradant fabric, at a defined force in the form of a Lissajous figure, with the test specimen able to rotate easily around an axis through its centre, perpendicular to the plane of the test specimen. Fuzzing, pilling, and matting are assessed visually after defined stages of rub testing.

Test equipment: Smartindale Martindale Abrasion and Pilling Tester

Martindale abrasion and pilling testers are suitable for testing the abrasion resistance and pilling degree of knitted fabrics, woollen fabrics, artificial leather, synthetic leather, etc. under pressure, which is used in many industries such as textile, footwear, and garment.

Because of the unique design of our Martindale abrasion and pilling test machine, you can remove individual sample holders for inspection without lifting the top motion plate. It provides individual counters and parking functions, interval time settable, and a large touch-screen display.

The Martindale abrasion testing equipment is available with 4, 6, or 9 test positions. Standard sample holders and nine and 12kpa Weights are included.

Applicable standards

• ISO 12945-2 Textiles – Determination of fabric propensity to surface pilling, fuzzing or matting – Modified Martindale method
• ASTM D4970 Standard test method for pilling resistance and other related surface changes of textile fabrics: Martindale tester
• ASTM D4966 Standard test method for abrasion resistance of textile fabrics – Martindale abrasion tester method
• GB/T 4802.2 Textiles – Determination of fabric propensity to surface pilling, fuzzing or matting – Modified Martindale method
• JIS L1076 Testing methods for pilling of woven fabrics and knitted fabrics

The Martindale abrasion & pilling tester can also be used for abrasion testing.

• ISO 12945-1 Textiles – Determination of fabric propensity to surface pilling, fuzzing or matting – Pilling box method
• ISO 12947 Textiles – Determination of the abrasion resistance of fabrics by the Martindale method
• GB/T 21196 Textiles – Determination of the abrasion resistance of fabrics by the Martindale method

2 Circular locus method for testing the fabric pilling

Test principle: The specimens are rubbed with nylon brushes and fabric abrasives, or with fabric abrasives only, according to the prescribed method and test parameters. After certain conditions, the pilling performance is visually described and evaluated under the specified light conditions.

Test equipment: TF225 Circular Locus Tester

Circular Locus Tester, to determine surface deterioration and quality of fabrics (wool, chemical fibre, mixed, kitted and woven fabrics). Using an active friction system, the fabric is rubbed against a nylon brush and abrasive or abrasive only under controlled conditions. The results of the test are achieved in minutes. The relative motion of the locus specimen grip and the abrasive platform is a circle with a relative speed of 60+/-1 r/min. The grip offers pressure to the specimen which is adjustable with a tolerance of +/-1%. For added control and safety, the machine is equipped with a self-stop switch.

Tests are carried out according to the test parameters in the table below, depending on the type of fabric.

Parameter type	Pressure / cN	Fuzzing times	Pilling times	Applicable fabrics
A	590	150	150	Workwear fabrics, sportswear fabrics, tight and heavy fabrics.
B	590	50	50	Synthetic outerwear, filament fabrics, etc.
C	490	30	50	Military garment fabrics, etc., combed blends.
D	490	10	50	Chemical fibre blends, interwoven fabrics, etc.
E	780	0	600	Combed woollen fabrics, short fibre braids, underwear fabrics, etc.
F	490	0	50	Combed woollen fabrics, pile fabrics, loose-structured fabrics, etc.

Applicable standard

GB/T 4802.1 Textiles – Determination of fabric propensity to surface fuzzing and to pilling – circular locus method

3 Pilling box method for testing the fabric pilling

Test principle: The specimen is mounted on a polyurethane tube, placed in a cork-lined wooden box and tumbled at a constant speed. After a specified number of tumbles, the pilling performance is evaluated by visual description. Any special treatment of the samples (washing, cleaning) should be agreed by the parties concerned and should be described in the test report.

Testing equipment: TF223 ICI Pilling and Snagging Tester

ICI Pilling Box, or ICI Pilling Tester, is suitable for detecting the pilling phenomenon caused by friction on the fabric surface without pressure, applicable to woven and knitted fabrics. TESTEX ICI Pilling Tester TF223 complies with ISO12945-1, NEXT TM19, BS 8479, JIS L1058, etc. Contact us for more information about the ICI pilling test method.

Applicable standards

• ISO 12945.1 Textiles – Determination of fabric propensity to surface pilling, fuzzing or matting – pilling box method
• GB/T 4802.3 Textiles – Determination of fabric propensity to surface fuzzing and to pilling – pilling box method
• JIS L1058 Test method for snag of woven fabrics and knitted fabrics
• BS 8479 Textiles – Method for determination of propensity of fabrics to snagging – rotating chamber method

How to assess the level of fabric pilling?

The tested specimens and one untested specimen are placed side by side on the specimen board of the pilliscope assessment viewer. To prevent direct lighting, each specimen is graded by looking directly at it from the front of the specimen at the edge of the rating box.

Rate	Description
5	No pilling
4	Slight pilling
3	Moderate pilling, pilling of different sizes and densities covering part of the surface of the specimen.
2	Severe pilling, pilling of different sizes and densities covering a large part of the surface of the specimen.
1	Very severe pilling, pilling of different sizes and densities covering the entire surface of the specimen.

Common finishing methods for anti-pilling textiles

For some fabrics that are prone to pilling, which affects the performance of use, the textiles can be treated with an anti-pilling finish where the raw material and tissue structure are limited.

1 Acrylic resin finishing

Acrylic resin finishing has a certain bonding effect on the fibres and yarns, increases the friction of the yarn, reduces fibre slippage and has a certain improvement on the pilling performance. The disadvantage is that most of these substances are anionic and cannot be used at the same time as softener, which has a significant effect on the feel of the fabric.

2 Reactive polyurethane finishing

Polyurethane can cross-link with the active genes on the fibres, or a self-cross-linking reaction, forming a protective film on the surface of the fibres, significantly reducing the wandering of the fibres, increasing the surface friction, thus achieving an anti-pilling effect, the disadvantage is the large amount and high cost.

3 Modified silicic acid polymer finishing

Modified silicic acid polymer is a cationic sol-gel type substance with a small particle size, typically 30-50 nm. With a high surface area ratio, the modified silicic acid polymer can effectively penetrate the internal fibre surface of the yarn to form a gel, significantly improving the friction coefficient of the fibre surface and enhancing the anti-slip effect of the yarn. As polysilicicic acid itself has good anti-static properties, the anti-pilling performance is ideal, and the excellent washing resistance has little effect on the feel of the hands and hardly affects the fastness of the dyeing.