Location: Cotton Structure and Quality Research
2017 Annual Report
Objectives
Objective 1: Enable, from a technological standpoint, new rapid and accurate commercial methods to assess cotton fiber quality.
Objective 2: Enable economical, accurate and real-time methods to assess product quality and process efficiencies in pre-mill operations.
Objective 3: Enable new commercial methods to detect, quantify and remove undesirable non-lint materials such as various sugars, seed coat fragments, non-leaf plant trash, etc. from cotton.
Objective 4: In collaboration with industry partners, determine the impact of fiber quality and fiber processing practices on yarn and fabric quality and processing efficiencies.
Objective 5: In collaboration with industry partners, determine the expected impact of new germplasms, agronomic practices, and ginning practices upon fiber quality, textile processing efficiency, and final product quality.
Approach
The U.S. cotton and textile industries agree on the need to increase U.S. cotton’s value and global competitiveness. It is proposed that this need be met by enabling new technologies and methods for accurately assessing the quality and processing efficiencies of cotton fiber at various processing stages from field to fabric. The first objective addresses the need for new rapid and accurate fiber quality assessments in the laboratory. Comprehensive evaluations will be conducted to broaden the technical and commercial attractiveness of image analysis, spectroscopy, microscopy, and color technologies to discern new measurements, with initial emphasis on 3-dimensional color, maturity, fineness, fiber diameter, fiber structure, and the relationship of these properties to key fiber quality properties. The second objective addresses the need for economical, accurate and real-time methods to assess product quality and process efficiencies outside of the laboratory in pre-mill operations. Comprehensive evaluations with state of the art spectroscopy and imaging instrumentation will be conducted to develop new quality measurement and monitoring methods for pre-harvest and post-harvest applications and operations. The third objective addresses the need for new assessments of non-lint materials and contaminants to provide improved tools for measuring, controlling and removing these non-lint materials. The development of rapid, accurate and non-destructive image scanning of seed coat fragments (SCF) and seed coat neps (SCN) will be developed, and these techniques will be used to understand what the AFIS is sensing when measuring SCN in fiber. Comprehensive evaluations with advanced chemical imaging spectroscopy technologies will be conducted to establish rapid detection and trash type identification protocols. State-of-the-art elemental analysis, chromatography, and spectroscopy technologies will be used to develop chemical measurements of fiber surface species, to include metal ions, sugars, amino acids/proteins, pectins, and waxes. These properties will be correlated to properties impacting fiber processing efficiency (i.e., stickiness and fiber friction). The fourth objective addresses the need for determining fiber quality-processing practices relationships and their impacts on product quality and processing efficiencies. In-house traditional and non-traditional quality measurements and textile processing will be used to determine the efficacy of these tests to predict processing efficiency and yarn/fabric quality and to understand the impact of fiber properties and processing on textile quality and efficiencies. The fifth objective addresses the need for determining the fiber quality-processing efficiency-product quality relationships. Comprehensive evaluations will be conducted on new germplasms using fiber quality and miniature-scale ring spinning. Advanced spectroscopic technologies will be used to characterize developing cotton fibers and their fine structure, their cell walls and physical properties.
Progress Report
This report covers work to develop and assess new quality measurements of cotton from the field to the finished textile product. Work has been performed to improve the measurement and understanding of traditional fiber quality parameters and non-traditional measurements. The needs of the textile industry have informed the work to ensure U.S. cotton remains the world’s first choice in cotton.
Cotton color measurement. Color is an important component of cotton quality. Typically, lint color is measured with a colorimeter, which reports an average value of reflected light and yellowness. Measurements were made by using image analysis to measure the distribution of color (Objective 1). This method allows for a rapid characterization of the variability of the color within a sample be it raw fiber or fabric. Variation in color within a sample has been correlated to “differential dyeing” results, which is a method for determining maturity-related dye defects in the textile industry. Variations of this procedure have been used to create software to detect barré, a shade difference in finished fabrics that is a common manufacturer complaint. The technique allows for an objective color value in lieu of subjective standards frequently used in industry. The next step in the research will establish criteria to better characterize color distribution to aid in the application of this technique.
Infrared measurements of cotton. Cotton bundles with a variety of moisture levels were examined with an infrared (IR) spectrometer (Objective 1). Changes in moisture content and distribution were observed. Changes were also observed based on the extent of cotton fiber development. This technique will be refined to provide a non-destructive tool for researchers to measure cotton fiber development.
IR spectroscopy was also used to determine the crystallinity and maturity of diverse cotton samples. Attenuated total reflection Fourier transform infrared (FTIR) spectroscopy was able to make a direct determination of fiber development in a rapid and non-destructive manner on single locules of cotton bolls (Objective 1). The technique is being used by scientists within the Fiber Bioscience Research Unit in New Orleans, Louisiana.
Ultra-small portable near infrared (NIR) spectrometers were used to measure micronaire (an industry value of combined maturity and fineness), maturity (cell wall development), and fineness (linear density) on ginned lint and seed cotton. Improved NIR models were developed to minimize the impact of temperature and relative humidity on the measurement (Objective 2). Validation is underway with cotton varieties from across the U.S. Seed cotton and ginned lint are measured on the portable NIR instrumentation in the laboratory and in non-laboratory conditions. Data from the portable NIR instrumentation is being compared with maturity and fineness distribution data collected from the Advanced Fiber Information System (AFIS) and CottonScope instruments, two instruments commonly used in the industry.
FTIR spectrometer with a high resolution detector was used to examine cotton fiber bundles and fiber development. The detector allows for the spatial examination of the bundles and provides indications of the sample distribution in the cotton bundle (Objective 4). Certain parameters were identified as markers of fiber development. Results suggest that these markers can be used to estimate cotton fiber maturity. Work continues to interpret these results.
Non-lint content characterization. Cottons with various levels of seed coat fragments were measured using the Advanced Fiber Information System (AFIS) and reference techniques. Results of the methods were used to understand what the AFIS is sensing as it measures seed coat fragments (Objective 3). Samples were analyzed before and after AFIS separation to better understand the AFIS particle classification. Image analysis of the raw and separated samples was carried out by the Agricultural Marketing Service (AMS) to understand the visual classing of seed coat fragments and other extraneous matter in ginned lint. This work is considered complete at this time.
Leaf grade is a score of the amount of non-lint content in a cotton sample during classification. The impact of leaf grade on processing in the textile mill is understood; it is less clear how the presence of non-lint material may alter the testing of cotton. Research was conducted to use image analysis to identify the components of non-lint content (Objective 3). Studies were carried out to conduct High Volume Instrument (HVI) testing of cotton samples before and after cleaning. The impact on measurement of micronaire (an industry measure of cotton fineness and maturity) repeatability due to non-lint content was shown to be significant for samples containing large levels of non-lint content. The ability of image analysis to identify constituents of non-lint content can be exploited to develop the next generation of cotton instrumentation.
Surface characterization of cotton fiber. Samples were collected for the measurement of chemical compounds on and within the cotton fiber. Samples have been analyzed for metal ions, waxes, sugars, pectins and amino acids (Objective 3). These compounds have been shown to vary with variety and agronomic conditions, and they influence textile processing and dyeing. The methods used for these analyses have been improved by reducing the measurement time so that the influence on fiber quality and processability may be studied on a larger sample set in a practical manner.
Excessive sugars found in the excretions from insects can lead to an issue known as “sticky cotton”. Samples have been collected from commercial collaborators. Samples were tested using several existing methods. The existing methods each use a different basis for testing such as physical processing (minicard), heat (thermodetector) and sugar composition of fiber (ion chromatography) (Objective 3). The agreement between the existing test methods is low. Ongoing research is demonstrating the deficiencies with current high-speed methods in order to inform and direct further work to develop a practical and accurate test method.
The role of surface friction in controlling the movement of fibers is important to produce high quality yarns. Samples have been produced in a controlled manner to have known values for surface chemical components, length parameters and fineness distributions. The frictional forces of these samples have been measured using a draftometer (Objective 3), which measures the force required to slide (or draft) the fibers past one another. Understanding these forces will allow for better determination of the attributes that affect surface friction and textile processing. A side effect of this work has been the discovery of a relationship between the energy needed to gin cotton and the energy needed to process the lint into yarn with the frictional characteristics of the cotton. This relationship is important because energy is the largest expense in the ginning of cotton and the second largest expense in textile processing. As fiber friction is better understood, the knowledge will be applied to reduce energy use in cotton processing.
Textile processing trials were conducted to demonstrate the role that various fiber quality parameters have on the processing of cotton fiber. Fiber samples were gathered representing all regions of the U.S. as well as various agronomic practices, such as variation in irrigation, harvesting and ginning. The tests were able to highlight the impact of these practices even in cases when traditional fiber quality measurements were unable to detect differences (Objective 4). Novel measurements, such as the Lower Half Mean Length (LHML) and draftometer measurements detected differences in fiber quality between samples that were not detected during routine testing but did appear during textile processing. Improved measurements are needed as cotton production practices change, new varieties have different properties and the end-use for U.S. cotton has shifted from domestic to international textile mill consumption. Most notably, as cotton yields have increased the physical diameter of the fiber has increased and this has been shown to be measurable by newly developed fiber fineness techniques more accurate than traditional techniques. The coarser fibers have been shown to limit the fineness of the yarn that can be spun, and impact the dyeability of the final textile product. The efficacy of new measurement techniques must be validated by demonstrating the utility of the measurement in textile processing.
Over 700 samples from the National Cotton Variety Trials (NCVT) were subjected to fiber testing and processing. Results were reported back to the NCVT committee for dissemination to the public to allow producers to make planting decisions and other researchers can explore the data for historic trends. Fiber samples from the NCVT will continue to be used as research materials for other parts of the project plan (Objective 5).
Processing trials were carried out on samples produced using ARS-developed high speed roller ginning (HSRG). HSRG has been reserved for extra long staple cotton (high quality cotton), however the increase in fiber length when roller ginning upland (short-staple) cottons opens up new markets for cotton (Objective 5). HSRG equipment is found exclusively in the western U.S. cotton regions and work focused on demonstrating the gains in processing (higher quality, faster production speeds, and finer yarn counts) that mills can achieve by utilizing HSRG upland cotton. The impact of processing cottons from the Delta and Southeastern regions with HSRG was also studied.
Accomplishments
1. Determination of the impact of environmental conditions on indirect measurements of cotton micronaire. Micronaire is a key cotton property, which is a combination of maturity and fineness that impacts processing and textile quality. Previously, ARS scientists had demonstrated that micronaire could be measured using near infrared (NIR) spectroscopy outside the laboratory; however the uncontrolled environment led to discrepancies in the results. ARS researchers in New Orleans, Louisiana, demonstrated that environmental conditions had reduced impact when benchtop instruments were used. When portable instruments were used, the impacts were larger due to the limited range of frequencies measured. These findings demonstrate that the use of portable instruments can be improved by the inclusion of moisture correction during calibration to overcome the limited range of the portable instruments. This work enables the non-destructive measurement of micronaire using NIR technology in the field by cotton breeders, producers and ginners.
2. Cotton fiber maturity and crystallinity determination. ARS researchers at New Orleans, Louisiana, developed and implemented an attenuated-total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy procedure to determine the maturity and crystallinity of cotton fibers at any growth stage using the reflectance of infrared light waves. The newly developed procedure takes less than five minutes for measurement of both crystallinity and maturity and requires only a small sample. The method has been cross-validated with other techniques. The rapid testing time and small sample size makes this technique beneficial for cotton researchers to monitor structural development of cotton fiber, such as changes in maturity and crystallinity.
3. Reduction of plastic contamination due to module unwrapping. Currently, cotton modules are wrapped in plastic for delivery from the field to the gin. This process helps to preserve cotton quality and reduces transportation costs, but it exposes the cotton to additional plastic, and complaints about plastic contamination in U.S. cotton bales are on the rise. ARS researchers at New Orleans, Louisiana, completed a survey across the U.S. and Australia cotton production areas to assess bale unwrapping systems to minimize the risk of plastic contamination and to access the economic and safety of these systems. Differences in how the unwrapping systems handle the modules were found that impact the potential for plastic to enter the material stream. This survey allows cotton ginners to make informed decisions about handling plastic wrapped modules from the aspects of contamination prevention, cost, speed and safety; and demonstrates the commitment of the U.S. cotton industry to address the rising incidence of plastic contamination.
4. High-speed roller ginning of upland cotton results in superior quality yarn production. Most upland cotton is ginned using saw gins. Although saw gins cause more fiber damage, they are much faster than roller gins. High-speed roller gins were designed by ARS scientists in Mesilla Park, New Mexico, to address the speed limitations. This technology was adopted by extra-long staple cotton producers, but not the far more common upland cotton producers and ginners. ARS researchers in New Orleans, Louisiana, demonstrated that the increase in fiber length and length uniformity afforded by high-speed roller ginning allowed finer yarns to be produced at a higher processing rate than could be produced by saw ginning. The higher processing rates help offset the increased cost of high-speed roller ginning. The ability to produce finer yarns opens up additional export markets where the demand for longer fiber length and improved uniformity has pushed customers towards foreign cotton sources.
5. Cotton bundle composition visualized by chemical imaging. Cell wall development is an important step in the growth of cotton fibers and directly impact fiber strength and dyeability. Infrared spectroscopy can be used to examine cotton fiber properties, such as micronaire and maturity. Previous studies relied on time-consuming point by point examinations. ARS researchers in New Orleans, Louisiana, have used a high-resolution infrared detector to create visual images of cotton fiber bundles. This visual representation of the sample allows breeders and researchers to examine the development of the fibers to better follow changes in cell wall development. Improved understanding of cotton cell wall development will lead to the production of improved cotton varieties that have fibers which are stronger and absorb dye more consistently.
Review Publications
Kuang, X., Guan, S., Rodgers III, J.E., Yu, C. 2017. Study on length distribution of ramie fibers. Journal of Textile Institute. doi:10.1080/00405000.2017.1297014.
Delhom, C.D., Armijo, C.B., Hughs, S.E. 2017. High quality yarns produced via high-speed roller ginning of upland cotton. Journal of Cotton Science. 21:81-93.
Gordon, S.G., Rodgers III, J.E. 2017. Cotton fibre cross-section properties. In: Gordon,S.,Abidi,N.,editors. Cotton Fibres: Characteristics, Uses and Performance. Hauppauge, New York: Nova Science Publishers,Inc. p. 65-86.
Santiago Cintron, M., Montalvo, J.G., Von Hoven, T.M., Rodgers, J.E., Hinchliffe, D.J., Madison, C.A., Thyssen, G.N., Zeng, L. 2016. Infrared imaging of cotton fiber bundles using a focal plane array detector and a single reflectance accessory. FIBERS. 4(27):1-11. https://doi.org/10.3390/fib4040027.
Van Der Sluijs, M.H.J., Delhom, C.D. 2016. The effect of seed cotton moisture during harvesting on - part 2- yarn and fabric quality. Textile Research Journal. Pg 1-7. doi:10.1177/0040517516659381.
Peralta, D.V., Fortier, C.A., Delhom, C.D., Rodgers III, J.E., Thibodeaux, D.P. 2016. Separation and quantitation of plant and insect carbohydrate isomers found on the surface of cotton. American Association of Textile Chemists and Colorists Journal of Research. 3(4):13-23. https://doi.org/10.14504/ajr.3.4.2.
Rodgers III, J.E., Zumba, J., Fortier, C.A. 2016. Measurement comparison of cotton fiber micronaire and its components by portable near infrared spectroscopy instruments. Textile Research Journal. p. 1-13 doi:10.1177/0040517515622153.
Zhang, R., Li, C., Zhang, M., Rodgers III, J.E. 2016. Shortwave infrared hyperspectral Imaging for cotton foreign matter classification. Computers and Electronics in Agriculture. p. 260-270. doi:1016/j.compag.2016.06.023.
Rodgers III, J.E., Zumba, J., Delhom, C.D. 2017. Microwave moisture measurement of cotton fiber moisture content in the laboratory. American Association of Textile Chemists and Colorists Journal of Research. 4(3):1-7. doi:10.14504/ajr.4.3.1.
Montalvo Jr, J.G., Von Hoven, T.M., Easson, M.W., Hinchliffe, D.J. 2016. Water, moisture and ash content of mechanically cleaned greige cotton, naturally colored brown cotton, flax and rayon. American Association of Textile Chemists and Colorists Journal of Research. 3(5):12-26.
Liu, Y. 2015. Rapid and routine assessment of cotton fiber cellulose maturity: current and future trends. Cellulose and Cellulose Derivatives: Synthesis, Modification, and Applications. p. 17-25.
Liu, Y. 2015. Near-infrared spectroscopy in the assessment of cotton fiber qualities. Agricultural Research Updates. 12:79-89.
Fortier, C., Santiago Cintron, M., Rodgers, J., Fontenot, K., Peralta, D. 2017. Fourier-transform imaging of cotton and botanical and field trash mixtures. Fibers. 5(20)1-11. https://doi.org/10.3390/fib5020020.
