Chemical Repellents Research Articles

Neuronal Responses of Antennal Olfactory Sensilla to Insect Chemical Repellents in the Yellow Fever Mosquito, Aedes aegypti.

The yellow fever mosquito, Aedes aegypti, is a vector of many human diseases such as yellow fever, dengue fever, and Zika. As insecticide resistance has been widely reported, chemical repellents have been adopted as alternative options for mosquito and mosquito-borne disease control. This study characterized the responses of olfactory receptor neurons (ORNs) in different types of antennal olfactory sensilla in Ae. aegypti to 48 chemicals that exhibited repellent activity in various insect species. Both excitatory and inhibitory responses were observed from ORNs in response to these chemicals and differential tuning properties were also observed among ORNs. Remarkable excitatory responses were recorded from the ORNs in sensilla SST1, SST2, SBTI, SBTII, and LST2, while inhibitory activities were detected from a neuron in sensillum SST2 in response to several terpene/terpenoid compounds. Moreover, the temporal dynamics of neuronal responses were found to be compound-specific and concentration-dependent. Hierarchical cluster analysis and principal component analysis of the response to each compound across ORNs in seven types of olfactory sensilla in Ae. aegypti revealed that odor reception depended not only on chemical class but also specific chemical structure. Results of this study give new insights into the sensory physiology of Aedes mosquitoes to the chemical repellents and should contribute to the development of new repellent reagents for human protection.

Phytochemicals as mediators for host range expansion of a native invasive forest insect herbivore.

Mountain pine beetle (MPB) has recently invaded jack pine forests in western Canada. This invasion signifies a climate change-induced range expansion by a native insect. The mechanism underlying this invasion is unknown, but likely involves phytochemicals that play critical roles in MPB biology. Thus far, studies have investigated the compatibility of jack pine chemistry with beetles and their microbial symbionts. I have identified three phytochemical mechanisms that have likely facilitated the host range expansion of MPB. First, jack pine chemistry is overall similar to that of the historical hosts of MPB. In particular, jack pine chemistry is compatible with beetle pheromone production, aggregation on host trees and larval development. Furthermore, the compatibility of jack pine chemistry maintains beneficial interactions between MPB and its microbial symbionts. Second, compared with historical hosts, the novel host not only has lower concentrations of toxic and repellent defense chemicals, but also contains large concentrations of chemicals promoting host colonization by MPB. These patterns are especially pronounced when comparing novel hosts with well-defended historical hosts. Finally, before MPBs arrived in jack pine forests, they invaded a zone of hybrids of novel and historical hosts that likely improved beetle success on jack pine, as hybrids show chemical characteristics of both hosts. In conclusion, the phytochemistry of jack pine has likely facilitated the biological invasion of this novel host by MPB.

Safe chemical repellents to prevent the spread of invasive ants.

The red imported fire ant, Solenopsis invicta, is one of the most dangerous invasive species in the world. Fire ants can spread by hiding among plant material and soil that are transported from infested areas in vehicles and vessels. Therefore, efficient repellents may be used to prevent fire ants from infesting transported goods. Although some fire ant repellants have been identified, novel, cost-effective and environmentally friendly materials for fire ant control are still needed. Recent studies with other model insects have suggested readily available, non-toxic alternatives (e.g., anthranilates) to commercial repellents. We measured the repellent effects of the food additives ethyl anthranilate and butyl anthranilate against nesting by fire ant workers, and the results demonstrated that extremely low concentrations of these compounds can prevent fire ant nesting in pots. The tested compounds remained active at concentrations < 100 µL/L, which is many times lower than the minimum active concentration of any other proposed compound, including the established insect repellent N,N-diethyl-3-methylbenzamide (DEET). These inexpensive chemicals are safely used by the food and cosmetics industries, and their high efficiency differentiates them as the most promising chemicals for use in preventing the spread of fire ants; thus, these chemicals should be evaluated for further potential applications. © 2018 Society of Chemical Industry.

Chemical composition and repellent activity of essential oils from the leaves of Cinnamomum zeylanicum and Eugenia uniflora against Diaphania hyalinata L. (Lepidoptera: Crambidae)

Diaphania hyalinata is an important pest in organic melon crops and has caused considerable harm to growers in northeastern Brazil. The aim of the present study was to determine the chemical composition of essential oils from Eugenia uniflora (pitanga) and Cinnamomum zeylanicum (cinnamon) as well as evaluate the repellant action, oviposition deterrence and effect on body mass caused by the oils and the constituents linalool and β-pinene in D. hyalinata. The essential oils from pitanga and cinnamon had a predominance of sesquiterpenes and phenylpropanoids, respectively. The pitanga oil was more effective as a larval repellent than the cinnamon oil and the constituents tested exhibited low repellent activity. In the evaluation of oviposition deterrence, the response of D. hyalinata exposed to the cinnamon oil did not vary with the distance between the treated and untreated leaf disks, but varied significantly when exposed to the pitanga oil. Linalool exhibited greater long-distance oviposition deterrence in comparison with β-pinene. In the experiments on body mass gain, second-instar larvae were more susceptible to the cinnamon oil than the pitanga oil and constituents tested. The findings suggest that these oils, especially the pitanga oil, could be an alternative for the control of D. hyalinata in the larval and adult phases. Further studies are needed to evaluate the effect on natural enemies and pollinating insects as well as the cost–benefit of the formulation of an insecticide for use on organic crops in northeastern Brazil.

Assessment of Barrier Materials to Protect Plants from Florida Leatherleaf Slug (Mollusca: Gastropoda: Veronicellidae)

Potential barrier materials (diatomaceous earth, hydrated lime, sulfur, fumed silica, wood ash) and chemical repellents (2 essential oil-based sprays) were evaluated for their efficacy to prevent herbivory by the Florida leatherleaf slug, Leidyula floridana (Leidy, 1851) (Gastropoda: Veronicellidae) by placing a band of material around the plant tissue or by direct application to foliage. Hydrated lime and sulfur effectively prevented foliage damage compared with the other 3 materials when presented as barriers. Dusting or sprinkling these barrier materials on foliage generally did not inhibit feeding by slugs, but sprinkling hydrated lime or wood ash onto foliage significantly reduced herbivory. Two commercially available essential oil formulations were evaluated for their effectiveness at repelling L. floridana. Pure ‘N’ Natural Snail & Slug Away (a cinnamon oil-based product) was quite effective whereas Slug & Snail Defense (containing cedar oil, pine oil, peppermint oil, and white pepper) was ineffective. Contact toxicities of barrier materials and essential oil products were assessed, and compared with a metaldehyde-based bait (Corry's Slug and Snail Pellets), an iron phosphate-based bait (Ecosense Slug and Snail Pellets), and a sulfur-based bait (Ortho Bug-getta Snail and Slug Killer2). Mortality of slugs was high when slugs were exposed to metaldehyde, hydrated lime, and the cinnamon oil-based spray. Iron phosphate bait, sulfur bait, and fumed silica were less effective but provided some reduction in herbivory. Soil moisture adversely affected efficacy of barrier materials, significantly compromising functionality relative to dry soils. Water uptake from soil by barrier materials was positively correlated with foliage consumption but pH was negatively correlated. Because of the negative correlation of pH with consumption, the negative effects of soil moisture on barrier effectiveness, and the rapid physiological response of slugs to some materials, these barrier materials are perhaps better considered to be physiochemical barriers rather than physical barriers.

Superamphiphobic and chemical repellent aramid fabrics for applications in protective clothing

This work aims to develop a facile two-step method for the fabrication of superamphiphobic and chemical repellent aramid fabrics. The aramid fabrics were coated with a formula consisting of waterborne polyurethane, poly(vinylidene fluoride-co-hexafluoropropylene) and fluoroalkyl silane via both a blade-coating process and an immersion technique. The wettability, surface morphology, thermal stability, chemical composition and chemical protective behaviors of the aramid fabrics were characterized. The coated fabrics showed contact angles of 157 ± 4° and 140 ± 2° for water and sunflower seed oil, respectively. No penetration was observed in coated fabrics stained with H2SO4, NaOH, and N,N-dimethylformamide for up to 150 min. The excellent repellent properties were retained after 10 washing cycles and 200 crocking cycles. Additionally, the coated fabrics showed superb restorable superamphiphobicity, demonstrating good potential to be used for chemical protective clothing.

Development of UV Protective, Superhydrophobic and Antibacterial Textiles Using ZnO and TiO2 Nanoparticles

In this research work, multifunctional cotton fabric comprising of UV protection, superhydrophobicity and antibacterial activity has been developed using facile pad-dry-cure method. In the first step, the concentration of repellent chemical has been optimized. Then, formulations containing nanoparticles of ZnO or TiO2 along with optimized concentration of repellent chemical and organic-inorganic binder have been applied to cotton fabric followed by the evaluation of functional properties. The surface morphology and elemental composition of treated fabric has been characterized through SEM and EDX, respectively. The treated samples have shown promising UV protection, superhydrophobicity and antibacterial properties durable upto 20 washing cycles.

Combined use of two defensive traits in pupae of Scymnus posticalis ladybirds

AbstractCoccinellid pupae have various defensive traits, such as keeping their final‐instar larval exuviae and secreting droplets containing defensive chemicals at the tips of glandular hairs. Although each of these traits has been described separately in different species, it is unclear how each defensive trait functions when more than one trait coexists. We found that pupae of the ladybird Scymnus posticalis have two different types of traits; they were partially covered with their own final‐instar larval exuviae, with thick wax structures, and had many glandular hairs secreting transparent droplets on the exposed parts of the body without waxy exuviae (head and medial parts of thoracic and abdominal dorsum). In this study, the defensive effects of these two traits were evaluated against two ant species, Tetramorium tsushimae and Lasius japonicus, which are potential predators. When encountering a pupa, neither ant species were able to make frequent physical contact with the exposed parts of the pupa because of the presence of the waxy exuviae. When touching the exposed body part that was covered with droplets, both ant species immediately stepped backward and then swept their antennae. The droplets suppressed ant feeding when mixed with sucrose solution, suggesting that the droplets contain repellent chemicals. These results indicate that the two traits of S. posticalis pupae (the larval waxy exuviae and the droplets) effectively play defensive roles against ants, functioning as a physical obstruction and a chemical repellent, respectively.

LARVICIDAL ACTIVITY OF LANTANA INDICA AND VITEX NEGUNDO ON CULEX QUINQUEFASCIATUS

Objectives: The activity of two different leaf extracts of Lantana indica and Vitex negundo is tested against the 3rd and 4th instar Culex quinquefasciatus larvae to evaluate the potency of the extracts as a larvicide and to find an ecologically sustainable alternative to chemical insecticides. A bioinformatics screening approach was performed to evaluate the in vivo results.Methods: The obtained larvae’s from nearby water sources were tested with N, N-diethyl-meta-toluamide (DEET) as the positive control which is the commercial chemical mosquito repellent and the solvents used for the respective plant extracts act as the negative control. Petroleum ether (PE), ethyl acetate (EA) and an aqueous (AQ) extract were prepared for both L. indica and V. negundo extracts, and its larvicidal activity was tested. A docking based approach was used to study the inhibitory effect of known active compounds from L. indica and V. negundo against acetylcholine esterase (AChE) and sterol binding protein as targets.Results: On comparing the results between three plants extract for its larvicidal activity, the EA extract of V. negundo and L. indica is found to be potent with a low LC50 value. Further, the docking studies between active compounds of L. indica and V. negundo with AChE and Sterol binding protein as targets showed that the compound tangeritin-1 had a good docking score compared to DEET and could be a natural alternative for larvicidal activity in the mosquito.Conclusion: Individual activity of tangeritin-1 could be further studied with mosquito mortality studies and molecular simulations and develop tangeritin-1 as a potential larvicidal compound for commercial use.

The elusive search for an effective repellent against voles: an assessment of anthraquinone for citrus crops

Vole (Cricetidae) girdling of tree trunks is a common form of damage experienced by tree and vine growers throughout much of the Northern Hemisphere. Management programs that effectively incorporate chemical repellents and vegetation management would be of substantial assistance to growers that experience such damage. Anthraquinone has proven effective as a repellent against voles in lab trials, yet controlled field tests of combined anthraquinone and vegetation management programs are lacking. Therefore, we established a mesocosm-based study in central California, USA, to test the efficacy of anthraquinone and vegetation management for reducing girdling damage caused by California voles Microtus californicus to Clementine citrus trees Citrus clementine under semi-field conditions. We observed a 90–100% reduction in girdling damage for trees following a single application of anthraquinone during two trials in summer and spring, respectively. Removal of vegetation around the base of trees further reduced damage during the summer sampling period, with no girdling observed on anthraquinone-treated trees that were surrounded by bare soil. We did not observe this same relationship during spring, and we observed no relationship between vegetation management in the absence of anthraquinone treatments in either seasonal trial, suggesting that vegetation management had a lesser impact on vole girdling than anthraquinone applications. We observed no decrease in efficacy of anthraquinone across the duration of both sampling periods (5–6 weeks), indicating substantial longevity for anthraquinone. Anthraquinone appears to have substantial utility for minimizing vole girdling damage. Field testing is warranted for additional mammalian species to determine potential uses for other taxa.

Efficacy of repellent-treated structural barriers for Richardson’s ground squirrels (Urocitellus richardsonii (Sabine)) and house mice (Mus musculus L.)

The worldwide presence of vertebrate pests such as rodents has created a need for non-lethal control methods that can be applied to integrated pest management plans. Chemical repellents are often a useful wildlife management tool as they can be directly applied to a commodity or structure to prevent infringement and damage. We assessed the efficacy of an anthraquinone (AQ)-based repellent in a structural barrier model against Richardson’s ground squirrels (Urocitellus richardsonii (Sabine)) (RGS) and house mice (Mus musculus L.). The AQ-based repellent was applied to pieces of burlap which were secured over each end of a small section of PVC pipe. Unadulterated enrichment food was then offered within the enclosed PVC pipe to motivate interactions with repellent-treated and untreated burlap barriers. Defeat of the barrier was defined as a physical breach by means of chewing the burlap or burlap/repellent barrier such that the test animal was able to gain entry to the hide and the enrichment food. RGS defeated 55% (±7.9) of untreated barriers, 25% (±6.8) of barriers treated with 50% dilution AQ-based repellent, and 27.5% (±5.6) of barriers treated with 0% dilution AQ-based repellent. House mice defeated 100% (±0.0) of untreated barriers, 20.5% (±6.4) of barriers treated with 50% dilution AQ-based repellent, and 45.5% (±7.8) of barriers treated with 0% dilution AQ-based repellent. Relative to untreated barriers, AQ treatments reduced defeat of the barrier by 50–55% for RGS and 55–80% for house mice. RGS showed a marked decrease in consumption of enrichment food after exposure to AQ. The 0% dilution of AQ-treated structural barrier had more individuals of both RGS and house mice chew through the structural barrier than the 50% dilution despite the increased concentration of AQ. We hypothesized that the additional water in the 50% dilution may have allowed for greater absorption of the repellent throughout the burlap fibers, thus enabling greater interaction with the AQ-treated barriers. Our results indicate that AQ-based repellents show promise as structural barriers for RGS and house mice.

Comparative Enactment of Fluorocarbon-free and Fluorocarbon-based Water Repellent Finishes on Cotton Single Jersey Fabrics

In this study, single jersey derivatives of knit fabric were taken to evaluate the performance of water repellent finishes on knit fabrics properties. Here, polo pique and single jersey knit structured fabrics were treated with different types of water repellent chemicals at different formulations. The levels of water repellency of the fabrics were measured in accordance with ISO 4920:2012spray rating test method. To assess the performance of water repellent finishes on knit fabric properties, GSM, bursting strength test according to ASTM (D 3786-87) method, color fastness to wash according to ISO- 105/ C06-C2S method, color fastness to water with ISO 105-E01 method and color fastness to rubbing with ISO-105-X 12 method were done. The results showed that the water repellent finish type and concentration were very important parameters to obtain water repellent fabrics with desirable properties.

Involvement of nociceptive transient receptor potential channels in repellent action of pulegone

Pulegone, one of avian repellents, is used to prevent the economic loss caused by birds. Chemical repellents often evoke unpleasant sensations and sensory irritation resulting in avoidance under some circumstances. It is recognized that some TRP channels expressing sensory neurons are related to nociception. Here we determined the molecular mechanisms of the repellent action of pulegone using isolated chicken sensory neurons and heterologous expression system. Pulegone increased the intracellular Ca2+ concentration ([Ca2+]i) in chicken sensory neurons. There were two types of neurons exhibiting different sensitivity to pulegone. One was responded to it at low concentrations and the other at high concentrations. Pharmacological analyses revealed that the former was predominantly mediated by TRP melastatin 8 (TRPM8), and the latter by both TRP ankyrin 1 (TRPA1) and TRPM8. An activation of both channels by pulegone was also determined using heterologously expression system. At high concentrations, pulegone suppressed chicken TRPM8 but not chicken TRPA1. The intraplantar injection of pulegone in chicks caused pain-related behaviors that were attenuated by TRPA1 antagonist. These results indicate that pulegone stimulates both TRPM8 and TRPA1 channel in chicken sensory neurons and suppresses the former but not the latter at high concentrations. Together, these data suggest that the molecular target for the repellent action of pulegone in avian species is nociceptive TRPA1.

Host-produced wax affects the searching behavior and efficacy of parasitoids of the giant whitefly Aleurodicus dugesii (Hemiptera: Aleyrodidae)

Insects possess a variety of defenses against natural enemies including physical attack, chemical repellency, physiological suppression, and visual camouflage. The hypothesis that wax production by the whitefly Aleurodicus dugesii Cockerell (Hemiptera: Aleyrodidae) functions as a defense against natural enemies was tested using two parasitoid species, Encarsia noyesi Hayat (Hymenoptera: Aphelinidae) and Idioporous affinis LaSalle & Polaszek (Hymenoptera: Pteromalidae). Parasitoids were allowed to forage on A. dugesii nymphs that had their wax either left intact or removed. Percent parasitism and the proportion of time spent grooming and searching were recorded and compared between treatments. There was a significant interaction between wax presence and parasitoid species on observed parasitism. Wax presence appeared to negatively impact I. affinis more than E. noyesi. In the presence of wax, the percentage of A. dugesii nymphs parasitized by I. affinis was reduced 30-fold, whereas E. noyesi parasitism was reduced 2-fold. Although both species spent more time grooming in the presence of wax, only I. affinis spent more time searching. The greater proportion of time devoted to these behaviors by I. affinis appeared to be due to its inability to remove wax particles from its body. The results from this study highlight the importance of considering whitefly-produced wax in mediating parasitoid-prey interactions. The differential impact of host defenses must be taken into consideration when selecting candidate natural enemies for biological control programs.

Potential of natural repellents methylanthranilate and anthraquinone applied on maize seeds and seedlings against house sparrow (Passer domesticus) in captivity.

Various bird pests caused severe economic losses to valuable crops and fruit orchards all over the world. Among the birds, house sparrow is also considered to cause heavy plunder, not only to seeds of crops but also seedlings especially in organic farming. In present study two bird repellents, methylanthranilate and anthraquinone tested against house sparrows on maize seeds and seedlings in aviary conditions. Trial group in aviary-I, the treated maize seeds and seedlings with different doses of both bird repellents, control group in aviary-II, untreated seeds and seedlings were provided for three hours in the early morning. In each aviary, two closed circuit cameras were also installed to monitor the behavioral responses against different concentrations of both chemical repellents. Statistical analysis showed that there existed highly significant (P<0.01) variations among the trial and control groups for seeds and seedlings. By comparing both repellents, significant (P<0.05) differences were detected and anthraquinone showed better efficacy when compared to methylanthranilate, but in maize seedlings both repellents equal repellent properties. Non-significant (P>0.05) differences were observed in different grading of both natural chemical repellents for maize seeds while significant (P<0.05) variations were noticed for maize seedlings when provided to sparrows. By videotaped behavior sparrows presented manifest head juddering and feather upsetting activities by consumption of treated seeds and seedlings with higher concentrations of both natural bird repellents.

A Pilot Qualitative Investigation of Stakeholders' Experiences and Opinions of Equine Insect Bite Hypersensitivity in England.

Equine insect bite hypersensitivity (IBH), commonly known as sweet itch or summer eczema, is a frustrating recurrent skin disease in the equine industry involving an immune reaction to the bites of Culicoides spp. midges. To investigate the impact of IBH in the field, an exploratory pilot study was conducted with equine stakeholders in one region of central England. Nine semi-structured, face-to-face interviews were conducted with horse owners and an equine veterinarian. The aim was to gain an understanding of experiences with IBH, and to gauge opinions on the value of the various management strategies horse owners use to control IBH. Awareness of IBH was generally high, particularly in those individuals who had previous experience with the condition. Those with previous experience of IBH commented on the significant effect on daily routines, and the associated cost implications. Most participants supported an integrated approach to hypersensitivity management, and this most commonly involved a combination of physical barriers and chemical repellents, but sometimes included feed supplementation. Overall, attitudes towards IBH suggested that the condition is a notable welfare and economic concern for stakeholders, but veterinary involvement tended to only be in more severe cases. Further research is required in the future to improve understanding, management and potential treatment of this condition.

Chemotactic droplet swimmers in complex geometries

Chemotaxis and auto-chemotaxis are key mechanisms in the dynamics of micro-organisms, e.g. in the acquisition of nutrients and in the communication between individuals, influencing the collective behaviour. However, chemical signalling and the natural environment of biological swimmers are generally complex, making them hard to access analytically. We present a well-controlled, tunable artificial model to study chemotaxis and autochemotaxis in complex geometries, using microfluidic assays of self-propelling oil droplets in an aqueous surfactant solution (Herminghaus et al 2014 Soft Matter 10 7008–22; Krüger et al 2016 Phys. Rev. Lett. 117). Droplets propel via interfacial Marangoni stresses powered by micellar solubilisation. Moreover, filled micelles act as a chemical repellent by diffusive phoretic gradient forces. We have studied these chemotactic effects in a series of microfluidic geometries, as published in Jin et al (2017 Proc. Natl Acad. Sci. 114 5089–94): first, droplets are guided along the shortest path through a maze by surfactant diffusing into the maze from the exit. Second, we let auto-chemotactic droplet swimmers pass through bifurcating microfluidic channels and record anticorrelations between the branch choices of consecutive droplets. We present an analytical Langevin model matching the experimental data. In a previously unpublished experiment, pillar arrays of variable sizes and shapes provide a convex wall interacting with the swimmer and, in the case of attachment, bending its trajectory and forcing it to revert to its own trail. We observe different behaviours based on the interplay of wall curvature and negative autochemotaxis, i.e. no attachment for highly curved interfaces, stable trapping at large pillars, and a narrow transition region where negative autochemotaxis makes the swimmers detach after a single orbit.

Bringing the Natives Back: Identifying and Alleviating Establishment Limitations of Native Hardwood Species in a Conifer Plantation

To facilitate the reintroduction of five native late-successional Taiwanese Fagaceae species into Japanese cedar (Cryptomeria japonica (D.) Don) plantations, we experimented with methods to alleviate their establishment limitations. We tested different combinations of tree species, seedling development stages, and site preparation techniques. First, we directly sowed both fresh and germinated acorns under both closed and opened (thinned) canopies. Both fresh and germinated acorns survived only six months at most. Wildlife consumption was the most critical factor hindering their survival. We subsequently experimented with different methods for increasing establishment rates, such as thinning in combination with understory control, applying chemical animal repellents to seeds, using physical barriers against seed predators, and using seedlings of different ages. Among the methods experimented, none was effective. The effects of silvicultural treatments to deter seed consumption lasted only the first few weeks after sowing, whereas the effects of physical barriers were inconsistent. We also tested planting 3-month and 1-year-old seedlings. Seedling survival after 9 months was about 20% on average for 3-month-old seedlings but reached 80% for 1-year-old seedlings. Our results suggest that planting seedlings older than six months or establishing physical obstacles to prevent seed predation will be the most effective strategies to reintroduce late-successional hardwood Fagaceae species into Japanese cedar plantations.

Use of 'cageless' barriers to enclose small starfish in short-term field experiments

Although small starfish may exert significant grazing effects on hard substrata, quantification of these effects has been difficult because of methodological limitations. Previously, caging small starfish for field experiments has failed because animals can escape through cage meshes and confounding effects may arise as the starfish can feed on organisms growing on the fences themselves, rather than the surface under investigation. Here, we investigated the efficiency of alternative barrier methods, such as antifouling paint and sticky barriers, for shorter-term experimental manipulation of the herbivorous starfish Parvulastra exigua. Laboratory and field manipulations tested the hypotheses that barriers are efficient in retaining starfish within plots and that the chemical repellent of the barriers does not affect the normal functioning of starfish. The results showed that the sticky barrier did not deter P. exigua, but antifouling paint retained greater numbers of individuals within barrier plots than in controls, with no short-term effects on starfish righting response.

Impact of Different Water Repellent Finishes on Cotton Double Jersey Fabrics

This study demonstrated that the variation in physical and chemical performance on cotton double jersey knit fabrics was decided by the knit structure, water repellent chemicals types and their concentration. Here, two types of double jersey fabrics were treated with different types of water repellent chemicals at different formulations to evaluate the performance of water repellent finishes on knit fabrics properties. The levels of water repellency of the fabrics were assessed by AATCC 127 hydrostatic head test method and by ISO 4920:2012 spray rating test method. To evaluate the performance of water repellent finishes on knit fabric properties, GSM, bursting strength test according to ASTM (D 3786-87) method, air permeability, color fastness to wash, water, perspiration, chlorinated water and color fastness to rubbing with ISO method were done. The results showed that both physical and chemical properties of the finished cotton knits, depend to a great extent on knit structure, the water repellent finish type and concentration to obtain water repellent fabrics with desirable properties.