Vartest Laboratories

FAST TURN COLOR ANALYSIS TESTING OF FIBER, YARN, FABRIC, APPAREL AND OTHER END USE ITEMS:

Adam Varley — Mon, 16 Jan 2012 14:03:28 +0000

Vartest offers fast turnaround time color analysis testing of fiber, yarn, fabric and end use items from its ISO/IEC 17025 accredited laboratory located in Midtown Manhattan. Spectrophotometers available include Dual Beam Sphere for use in retailer color management programs, 45° Illumination and 0° Viewing for fluorescent samples and Dual Beam Sphere with Near Infra Red capability for military programs. All of them are interfaced with state of the art color management and communication software.

These instruments provide objective, quantitative visual color measurement and assessment as well as shade sorting, shade grouping and banding, tapering, lab dip approval as well as objective rating of colorfastness test results such as crocking, laundering, light, storage and perspiration.

Vartest’s color quality control capability provides an Accredited Third Party backup to retailer, manufacturer and importer color management systems. QTX files can be generated and emailed by Vartest containing digital color information on standards, lab dips, production samples and fabric rolls destined for the cutting table.

Color Measurement Proficiency Interlab Results Displayed Electronically

Instrumental color measurement systems are operated by experienced technologists with specialized training in color measurement. The visual acuity of operators is checked using the Farnsworth Munsell color vision test in conjunction with Vartest’s calibrated Macbeth light boxes which are used for visual assessments when needed.

Polyester Fiber And Triexta Fiber Generic Subclass Testing Capability Enhanced

Adam Varley — Thu, 10 Nov 2011 16:22:46 +0000

Using a combination of analytical techniques as well as experience with weft knit, warp knit, woven and non woven textile structures, Vartest provides a unique capability for analyzing polyester fiber and the polymers which make them up including FTC designated polyester fiber subclasses and related fibers.

Preparing Vartest's FTIR Microscope For Textile Fiber Work With Liquid Nitrogen

The Federal Trade Commission covers but is not limited to three related polyester polymers used to produce textile fibers: Polyethylene terephthalate (often abbreviated as PET and the polymer which makes up the world’s most commonly used textile fiber), polytrimethylene terephthalate (FTC generic sub class triexta and also commonly known as PTT and with the current IUPAC name poly(propyleneterephthalate) and polybutylene terephthalate (often abreviated as PBT). The structures of PET, PTT and PBT are shown in the following ball and stick models:

Three Repeat Unit Chains Of Polyethyleneterephthalate, Polytrimethyleneterephthalate and Polybutyleneterephthalate

Fibers made of PTT may be labelled ”Triexta” however fibers composed of PBT do not have an FTC designated subclass and so can be labeled “Polyester” and be more fully characterized as PBT Polyester. Fibers made of PET are usually simply labeled as ”Polyester”.

The chief difference in chemical structure between these three polymer groups is the addition of a single methyl group to the polymer repeat with each of PTT and PBT. PET has two methyl groups in the hydrocarbon chain connecting phthalate esters, PTT three and PBT four. The addition of methyl groups leads to significant changes in fiber performance in end use, making PTT for example, particularly suited to end uses such as carpeting. The addition of methyl groups to the hydrocarbon chain also leads to decreasing melt point as seen in the following differential scanning calorimetry curves:

Differential Scanning Calorimetry Comparison Of PET, PTT and PBT

Micro Fourier transform infrared analysis helps to differentiate these polymer groups with clear separation of PBT, PTT and PET capable with even a single fiber and enabeling dissected filament yarns from a complicated structure such as a multi bar tricot warp knit to be positively identified both qualitatively and quantitatively as seen in the following light micrograph:

Once dissected micro FTIR spectra of the yarns above are obtained and run against a search library for identification. The image above shows the dissected PET top bar yarn of a 1-0/2-3 fully threaded tricot structure as well as the PBT 1-2/1-0 back bar. A micro Fourier transform infra red analysis of SmartStrand carpet fiber is shown below with a 95% Euclidean hit to a control sample of known triexta fiber:

Micro Fourier Transform Infra Red Analysis Of SmartStrand Triexta Fiber

Nuclear magnetic resonance (NMR) testing complements this work differentiating between PET, PTT and PBT as seen in the following Hydrogen-1 NMR and Carbon-13 NMR comparison done at 300 megahertz with deuterated trifluoroacetic acid as the solvent:

300 Megahertz Nuclear Magnetic Resonance Spectra

Vartest provides in depth analysis of all characteristics of fiber make up, morphology and performance assisted by a proprietary search library of thousands of fibers from all markets and end uses.

ANTIBACTERIAL PROFICIENCY TRIAL RESULTS SUPPORT ISO/IEC 17025 CAPABILITY FOR AATCC 147 AND AATCC 100

Adam Varley — Fri, 23 Sep 2011 19:31:34 +0000

Vartest has successfully completed participation in AATCC Proficiency Trials in support of ongoing ISO/IEC 17025 Accreditation for AATCC Test Methods 147 and 100. Additionally elemental analysis via wet chemistry/spectroscopy and energy dispersive xray are available in order to measure the presence and establish the location of elements such as silver which are associated with a particular anti bacterial finish.

Biosafety Level 2 Testing At Vartest

Antibacterial testing is often one component of a battery of tests that Vartest performs to fully characterize a textile product. Both leaching and non leaching finishes can be assessed and Vartest has full capability to analyse the substrate to which an antibacterial finish has been applied.

SERICIN AND FIBROIN SPECIFIC STAIN USED TO CHARACTERIZE SILK FILAMENTS

Adam Varley — Mon, 05 Sep 2011 15:49:16 +0000

Filament silk or bombyx mori silk is extruded from two seperate glands in the region of the spinerette on the silkworm’s head as it spins its cocoon. These two filaments are composed of beta pleated sheets of fibroin protein which are joined together by a sericin outer sheath which is simultaneously extruded from two other glands in the region of the silkworm’s spinerette.

The sericin outer sheath and fibroin inner region can be seen in the following low and high magnification scanning electron micrographs:

Scanning Electron Micrograph Of Woven Silk Fabric

Scanning Electron Micrograph of Sericin Coated Bave Containing Two Fibroin Brins

To further differentiate the sericin/fibroin interface Vartest has developed a stain which colors the sericin outer sheath purple and the fibroin filaments pink as seen in the following light micrograph:

The sericin surrounding the bave has been stained purple, the two fibroin brins pink.

The two fibroin filaments in combination with the sericin outer sheath is known as a bave, while the individual fibroin filaments are known as brins.

Vartest combines multiple testing and analytical techniques to fully characterize fibers both as manufatured and in end use.

STATISTICAL ANALYSIS AND CONTROL CHARTING OF INSTRON 5569 TENSILE TESTING USING INTERACTIVE VIDEO CAPTURE TO DEVELOP GLOBAL QUALITY CONTROL PROGRAMS

Adam Varley — Tue, 23 Aug 2011 21:42:03 +0000

Textile testing of cotton sheeting using the ASTM International D5034-09 Standard Test Method for Breaking Strength and Elongation (Grab Test) demonstrates the ability of the laboratory to characterize and provide corrective actions to manufacturers and importers based on the determination of assignable and common causes within the framework of a quality control program. Common causes of variation are those associated with everyday or typical on target mill performance. Assignable causes causes are those associated with a loss of control in the manufacturing process that can lead to production of products that fail important performance specifications.

The sample used comprised a plain weave square cotton sheeting whose structure is shown below using both reflected light and scanning electron microscopy:

Light Microscopy Micrograph Of Plain Weave Sheeting Fabric

Scanning Electron Microscopy Of Plain Woven Structure

Testing was performed on Vartest’s Instron 5569 load frame running Bluehill 3 software with real time video capture as seen in the following image:

Video Capture Provides The Ultimate In Specimen Performance Chracterization

A 100 specimen sample taken in the warp direction was tested on Vartest’s Instron 5569 Constant Rate of Extension Load Frame with interactive video capture as seen in following force elongation curves:

Specimens 1 through 25

Specimens 26 through 50

Specimens 51 through 75

Specimens 76 through 100

Breaking force was exported and plotted as a control chart which revealed specimens 20 and 85 displaying variation attributable to assignable causes:

Control Chart For Breaking Force

Elongation at break was also exported and plotted as a control chart which revealed specimens 19, 20 and 85 displaying variation attributable to assignable causes.

Control Chart For Elongation At Break

Investigation of video capture files for these specimens revealed slippage at the jaw due to intentionally induced gradually decreasing low air pressure being introduced into the pneumatic clamps as the cause of excessive variation in specimens 20 and 21:

For comparison the break characteristics of Specimen 5 showing only common cause variation is shown in the following video:

Specimen 85 was revealed to be a filling direction specimen that had been intentionally introduced into the test specimen series. While the breaking force of the filling specimen was about 30% lower than the mean, the elongation at break was about 300% higher than the mean; predominantly due to the high level of filling yarn crimp possessed by the filling specimen as opposed to the relatively low amount of warp yarn crimp possessed by the warp specimens as seen in the following video:

Variation in textile quality can be quantified and managed readily with statistical tools used in conjunction with standard test methods and performance specifications.

Gaussian Sort Of Tested Specimens

Assignable causes of variation in textile and apparel quality such as uneven application of water resistant finishes, antibacterial finishes and seam slippage performance can all be analyzed and corrected with the aid of these techniques. Accredited quality assurance laboratories inform and control factory supply chains worldwide.

For more information click here for Instron’s Website.

Announcing service expansions & equipment updates

admin — Wed, 02 Feb 2011 14:57:35 +0000

Vartest Laboratories continues to expand services for flammability, textile insulation and vapor resistance to facilitate performance assessment of safety and protective products and garments.

Vartest Laboratories demonstrates excellence in the services provided to high technology and compliance markets, while maintaining unsurpassed breadth of methods and capabilities to the textile, apparel, home textile, and industrial markets, and military sectors. We are continually improving our offerings through investment in the latest technology and ISO-17025 accredited operations.

Recent additions and updates to the laboratories included:

Installation of new instruments for Thermal and Radiant Protective Performance (TPP & RPP) to meet ISO, EN, NFPA, ANSI and military requirements.
Updating of basic instruments for ASTM 6413 and NFPA 701 flammability testing.
Isothermal Sweating Hot Plate instrumentation along with a broad scope environmental chamber and remote access technology.
Our GCMS section is also supported by high performance microwave digestion and rotary evaporation instruments.
Near Infra Red Spectrophotometry for measurement of spectral reflectance.
Updated hydrostatic penetration capability.
Running all methods all methods including ASTM D751.
IL options ISO 811, AATCC 127 and others up to 200,000 millimeters of water pressure.

With this expanded capability, Vartest provides highly specialized protective performance assessment of products and applications related to development and production of fabrications dedicated to military, active sportswear and other specialized markets, which require elevated performance in unique environments.

Vartest sets itself apart with in-house testing using a fully automated large scale goniometric range for evaluation of high visibility trims, including all treatments required by ANSI 107, 207, EN 471 and CSA 96 protocols. It is this dedication and continued investment that positions Vartest as the undisputed leader in color measurement and spectral data in .qtx format, high visibility assessment and third party certification and compliance verification of high visibility safety and protective products and garments.

We invite your enquires and look forward to meeting all of your company’s testing requirements and greatly appreciate the opportunity to do so.