Randall R. Bresee

Fabric Defect Detection and Classification Using Image Analysis

Conventional image analysis hardware was used to image solid-shade, unpattemed, woven fabrics. Two different software approaches for detecting and classifying knot and slub defects were studied and compared. The approaches were based on either gray level statistics or morphological operations. The autocorrelation function was used for both methods to identify fabric structural repeat units, and statistical or morphological computations were based on these units. Plain weave and twill weave fabrics were used to compare the performance of each software approach.

Near-Surface Analysis and Depth Profiling by FT-IR Photoacoustic Spectroscopy

Fourier transform photoacoustic spectroscopy (FT-IR/PAS) has proven to be a powerful technique for the near-surface characterization of solid materials. The effective sampling depth of FT-IR/PAS can be varied by using different interferometer mirror velocities, so that nondestructive depth profiling can be performed. In this research, sized cotton yarns, treated glass fibers, chemically modified poly(ethylene terephthalate) fibers, and a naturally weathered poly(vinyl chloride) composite were investigated with the use of FT-IR/PAS at different mirror velocities. Penetration of the chemical additives in these materials was studied. It was demonstrated that FT-IR/PAS has the ability to investigate the changes in chemical nature within the detectable surface layers of solid samples.

General Effects of Ageing on Textiles

AbstractGeneral effects of five types of ageing on textiles are examined. The types of ageing discussed are physical, photochemical, thermal, chemical and mechanical. Changes in the structure and properties of textiles that result from each type of ageing are discussed in general terms. This paper is expected to provide conservators of polymeric materials (textiles in particular) with a basic understanding of some of the more important changes in textiles that result from ageing.

Carbamate insecticide removal in laundering from cotton and polyester fabrics

Even though carbamate insecticides are becoming increasingly important for insect control on field crops, few studies have focused on their removal from contaminated textiles. Hence, this study evaluated the effectiveness of selected laundering procedures in removing carbofuran and methomyl insecticides from 100% cotton and 100% polyester medium weight fabrics. After treating the fabric samples with 4.0% (w/w) aqueous solutions of Furadan® 4F Insecticide (carbofuran) or Lannate® L Insecticide (methomyl), they were air dried and laundered, using three detergents [All® (non-ionic), Tide® (anionic), and Wisk® (anionic and non-ionic)] plus water only at two temperatures (warm: 49°C wash/40°C rinse and hot: 60°C wash/49°C rinse). The percentages of insecticide residue remaining on the fabrics after laundering were analyzed by high performance liquid chromatography (HPLC) with a fluorescence detector, and bioassay tests withDrosophilia malanogaster Meigen were used to evaluate their relative toxicity.All of the laundering procedures, including the water only wash, were effective in removing ⩾99% of the carbamate insecticides from both the cotton and polyester fabrics. Among the insecticide/fabric types evaluated, the highest percentages of residue remaining were associated with the polyester fabrics treated with methomyl. After 72 hr, fruit fly mortality occurred on only the methomyl treated polyester laundered in warm water. These findings support those reported in previous studies on the ease with which carbamate contaminants are removed from textiles, compared to other insecticide types.

FLEXIBLE MULTIFUNCTION INSTRUMENT FOR AUTOMATED NONWOVEN WEB STRUCTURE ANALYSIS

We have developed analysis tools to characterize nonwoven web structures based on image analysis techniques. Six analysis modules we previously reported are integrated into one automated instrument system. In this paper, we discuss hardware and software designs used to achieve instrument flexibility, automated operation, and multifunctional analysis capability. We hope this discussion will be useful to other people interested in textile instrument development and automated testing.

Characterizing Fuzz on Fabrics Using Image Analysis

A hardware device and software based on image analysis techniques are developed to detect and describe fuzz on fabric surfaces. Thin optical slices near the surface of fabrics are imaged with a microscope objective lens and electronic camera. Sharply focused fuzz fibers are detected within each image and described in terms of fuzz density, fuzz height, and fabric-fuzz separation. The hardware device and software techniques are evaluated by visualizing fuzz detection in individual images and by assessing the reasonableness of measured fuzz parameters for fabrics with intuitively known fuzz attributes. The instru ments usefulness is explored by assessing the influence of the yarn interlacing pattern, mechanical abrasion, and a fuzz-reducing finish on fuzz.

Studies of Chemically Modified Poly(ethylene terephthalate) Fibers by FT-IR Photoacoustic Spectroscopy and X-Ray Photoelectron Spectroscopy

Fourier transform infrared photoacoustic spectroscopy (FT-IR/PAS) and x-ray photoelectron spectroscopy (XPS) were used to determine the location of a copolymeric finish in poly(ethylene terephthalate) (PET) fibers. The XPS studies showed that the copolymeric finish was deposited on the fiber surfaces. The FT-IR/PAS data demonstrated possible penetration of the finish from the fibers surface into the near-surface. The combination of FT-IR/PAS and XPS appears to be very useful for the determination of finish location in chemically modified fibers.

Influence of Textile Structure on Single Fiber Transfer from Woven Fabrics

A machine designed to abrade fabrics using small abrasive forces and slow rates is used to induce fiber transfer from twelve woven fabrics. Single fiber transfer, the release and relocation of individual fibers, is evaluated in terms of the number and length of fibers transferred, along with the influence of several fiber, yarn, and fabric structural features on fiber transfer. Modeling procedures indicate that structural features that predict fiber transfer best are fiber denier, fiber length, and weave type. The influence of these features is complex, and analysis of variance indicates that fiber transfer is significantly affected by their interaction.

Studies of Sized Cotton Yarns by FT-IR Photoacoustic Spectroscopy

Cotton yarns treated with polymenc sizing agents were studied by Fourier trans form infrared photoacoustic spectroscopy (FT-IR/PAS). Sizing agents on the yarn surfaces were identified by the use of spectral subtraction. The degree of penetration of the sizing agents into the yarns, the amount of sizing agents remaining in the yarns after desizing, and the hydrogen bonding between the sizing agents and the cotton cellulose also were investigated by FT-IR/PAS. In this research, the photoacoustic de tection demonstrated a variety of advantages over the conventional infrared spectro scopic sampling techniques.

Enriched copper isotope tracer for dietary copper incorporation into hair using neutron activation analysis in conjunction with direct-current argon plasma spectrometry

Abstract A method is described for labeling and measuring the incorporation of dietary copper into hair using the enriched (99.61 atomic-%) 65Cu isotope. Natural isotope abundant copper exists as 65Cu (30.86 atomic-%) and 63Cu (69.17 atomic-%), but enriched (99.61 atomic-%) 65Cu isotope may be obtained commercially and administered to change deliberately the natural isotope abundance of copper to “label” the copper source. Natural isotope abundant copper and the enriched (99.61 atomic-%) 65Cu isotope were mixed into rat feed and administered daily by gavage. The isotope concentration was determined by neutron activation analysis (NAA). The copper concentration was determined by direct-current argon plasma (DCP) spectrometry. The measured copper isotope ratios (65Cu/Cutot)_for the natural isotope abundant copper in National Bureau of Standards Standard Reference Materials (NBS SRM) 1571 Orchard Leaves and 1577a Bovine Liver were 0.3201 ± 0.0039 and 0.3187 ± 0.0089, respectively. Measured copper isotope ratios in rat hair were 0.3100 ± 0.0606, 0.4580 ± 0.2495 and 0.2712 ± 0.0645 from rats given a standard feed that contained natural isotope abundant copper, a daily supplement of natural isotope abundant copper sulfate mixed into the standard feed and a daily supplement of copper sulfate administered by gavage, respectively. The copper isotope ratio increased to 0.5251 ± 0.2860 and 0.7235 ± 0.0704 in hair from rats given enriched 65Cu in their feed and by gavage, respectively. The statistically significant increase in the 65Cu isotope when administered by gavage demonstrates strates successful labeling of dietary copper in the hair.