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Suntech non-woven quality inspection methods and standards.
During the covid-19 epidemic, masks were in short supply. Non-woven fabrics are an important raw material for making masks. As a result, the demand for non-woven fabrics has surged. More than 3,000 companies have to cross-border mask production industries. The uneven industry status also gives non-woven fabrics. Testing brings challenges. What kind of non-woven fabric is qualified? What are the testing standards?
Non-woven fabrics are also called non-woven fabrics and non-woven fabrics. Is composed of oriented or random fibers. It is called cloth because of its appearance and certain properties. Non-woven fabric has the characteristics of moisture-proof, breathable, flexible, light weight, non-combustible, easy to decompose, non-toxic and non-irritating, rich in color, low price, and recyclable. For example, polypropylene (PP material) pellets are mostly used as raw materials, which are produced by continuous one-step method of high-temperature melting, spinning, laying, and hot-pressing coiling.（Click to share to LinkedIn）
The scientific name of non-woven fabric is non-woven fabric, so the standard of non-woven fabric is mostly named after non-woven fabric. The non-woven fabrics used in the production of masks are mostly polypropylene spunbonded non-woven fabrics and polyester non-woven fabrics. Here we recommend to refer to the textile standard FZ/T 64033-2014 "Spunbond Hot Rolled Nonwoven Fabric".
According to the regulations in FZ/T 64033-2014, the internal quality inspection items of mask non-woven fabrics mainly include width deviation, mass deviation per unit area, coefficient of variation of mass per unit area, breaking strength, and elongation at break. The appearance quality inspection items mainly include color difference, defective edge trimming rate, joints, frit, foreign matter, defective rate of auxiliary net, soft folds, etc.
Of course, since there is no clear standard, suntech has proposed several important test indicators based on previous mask testing and non-woven testing experience, namely filtration efficiency, respiratory resistance, hygiene indicators, and toxicology tests.（Click to share to Facebook）
1. Filtration efficiency
As we all know, filtration efficiency is a key indicator for the quality evaluation of masks. This is also one of the important quality standards of non-woven fabrics, so referring to relevant standards, we recommend that the bacteria filtration efficiency of mask non-woven fabrics should be no less than 95%, and the filtration efficiency of particles should not be less than 30% for non-oily particles.
2. Breathing resistance
Respiration resistance is the size of the influence that hinders breathing when people wear a mask. Therefore, the breathing resistance of the mask non-woven fabric determines the breathing comfort when wearing the mask. The index we recommend here is that the inhalation resistance should be ≤350Pa and the expiration resistance should be ≤250Pa.
3. Sanitary indicators
Sanitary indicators are naturally another important key indicator of non-woven masks. Here we recommend testing items mainly including initial contaminating bacteria, total bacterial colonies, coliforms, pathogenic pyogenic bacteria, total fungal colonies, Escherichia coli, Staphylococcus aureus, Candida albicans, ethylene oxide residues, etc.
4. Toxicology test
The skin irritation test mainly considers the protective test test for people who are allergic to some materials. Refer to the regulations in GB 15979. The skin irritation test of the mask non-woven fabric is mainly to cut a sample of a suitable area, soak it with normal saline, and paste it on the skin, and then cover it with a patch sticker for testing.
Among the above indicators, the filtration efficiency of non-woven fabrics is the most important. The specific detection method can refer to the two standards of YY/T 1497-2016 "Medical protective mask material virus filtration efficiency evaluation test method Phi-X174 phage test method", YY/T 0866-2011 "Medical protective mask total leakage rate test method" these two standards .（try suntech Non-woven fabric）
The following are the non-woven fabric testing standards proposed by the world's leading associations in non-woven fabrics and related industries and on behalf of EDANA.
Nonwovens Standard Procedures
What are Nonwovens Standard Procedures?
In 2005, EDANA and INDA, the leading global nonwovens associations, started to jointly publish the nonwovens standard procedures for the nonwovens and related industries.
Every 3 years a new updated version was released. In 2018 it was decided to change this periodic review into a continuous review. This allows amendments to be published directly instead of waiting till the next release. This of course is only possible through on-line publishing. As a consequence, we don’t publish a complete compilation of all methods in a single file anymore.
This resource, developed in partnership by INDA and EDANA, helps define, in a technical sense, the nonwovens industry, with specifiers for the properties, composition and specifications of its products. The NWSP offers harmonised language for the industry across the USA and Europe, and recognised by many other individual markets, while the procedures offer a way for the nonwovens industry to communicate both across the globe, and within the supply chain to ensure that product properties can be consistently described, produced and tested.
The Nonwovens Standard Procedures offer methods to test the structure and performance of nonwovens and related materials, many of which have been developed by the industry, and adopted by ISO or CEN.
How are the Nonwovens Standard Procedures classified?
The following format has been adopted:
NWSP 000.0.R0 (15) where the first three digits followed by one or two digits after the dot identify the method; the number after the R refers to the number of revisions (changes that affect the test procedure) that have occurred since the 2005 launch; the number in parenthesis refers to the year of the last review. If needed, the history of any given test method before 2005 is available from either EDANA or INDA.
In the table of content, you will find Normative References (ISO standards) next to the NWSP procedures. By highlighting the existence of an internationally recognised ISO standard, member companies can decide which procedure to apply (ISO or NWSP). Keep in mind, ISO and NWSP methods do not undergo revisions at the same time and differ in their lay-out.
How to get a copy of the Nonwovens Standard Procedures
The Nonwovens Standard Procedures are available - free of charge- to EDANA members on the EDANA member portal. In the Document module, type “actualNWSPs” in the search bar and all methods will appear as well as the Table of Content (that includes hyperlinks to directly pre-view the individual methods).
Main inspection items of non-woven fabrics
1. Color fastness test: color fastness to washing, color fastness to rubbing (dry, wet), color fastness to water, color fastness to saliva, color fastness to light, color fastness to dry cleaning, color fastness to perspiration , Color fastness to dry heat, color fastness to heat pressure, color fastness to chlorine water, color fastness to scrubbing, color fastness to chlorine bleaching
2. Physical performance testing: tensile breaking strength, tearing strength, seam slippage, seam strength, bursting strength, anti-pilling resistance, abrasion resistance, fabric density, weight, thickness, width, weft skew , Yarn count, moisture regain, single yarn strength, appearance after washing, dimensional stability
3. Functional testing: air permeability, moisture permeability, combustion performance, waterproof performance (hydrostatic pressure, splashing water, rain), electrostatic testing
4. Chemical performance testing: PH value determination, composition analysis, formaldehyde content, azo test, heavy metals.
With 50 years of technical precipitation and design experience, suntech has developed and produced intelligent non-woven machines, including spunbonded non-woven machine, spunmelt non-woven machine, melt blown machine, etc. The non-woven fabrics produced can meet various standards , We also produce non-woven fabrics, welcome all kinds of non-woven fabrics and non-woven machines to customize.