Fabric & Garments FinishingAssignment 3 - Insect Repellent Finishes

By :- Bittu Singh Presented to :- Mr. Amit Phogat

Radhe Kumar

Shubham Singh

Introduction

Natural textile fibres - made up either of carbohydrates(cellulose) or proteins(keratin and fibroin)

Both - serve as food for living organisms - bacteria, fungi, mildew, insects, moths etc. - chemically damaged - loss of strength, discoloration etc.

Protection against this damage - antibacterial, fungicidal, anti-mildew, insect proofing, mothproofing, rot proofing treatments have to be imparted.

Wool moth proofing agents - innocuous to aquatic life, resistant to washing and dry-cleaning, perspiration and to prolonged exposure to light

Dieldrin - applied to wool, along with dyes by various methods using exhaustion process (low concentration) - durable mothproofing effects

Complete exhaustion of the toxic substance(dieldein) - not possible and the residual substance finds its way in the effluent - extremely toxic to fish

It is applied by padding.

Partial solution - in padding process, the amount of liquor employed is much less than in the exhaustion process

New process of application of dieldrin to woollen fabric - Undyed, scoured woollen fabric and Dieldrin Carrying Fixative(DCF) which contains a fixative was used

Application Process

Fabric - padded(100% pickup) with a dispersion of DCF in water in room temperature - drying at elevated temperatures

Eulan New - Commercial mothproofing agents of Bayer - followed by EulanCN Extra

Effective insect proofing of wool - 3% and 2% of Eulan New and Eulan CN Extra respectively have to be used - may be applied under acidic conditions at the boil and may be added to the dyebaths containing acids dyes.

Application Process

Comprise a series of synthetic insecticides - structures similar to pyrethrins -natural insecticides found in flower heads of pyrethrum plants(chrysanthemum cinerariae)

Pyrethrin - insecticidal components of pyrethrum extracts

Has low mammalian toxicity(to human beings) - high insecticidal activity -photochemical and hydrolytic stability

Permethrin based wool mothproofing agents - Perigen, Mothproofing agent 79(Shell), Mitin AL(Ciba-Geigy) & Eulan SP(Bayer)

Reagent used : Pyrethroids

Quaternary ammonium salts - impart protection to wool against black carpet beetles & moth larvae

Product made by condensing p-tert. octyl phenol with dichloro-diethyl ether - then converting the resulting mono-choloro compound into a quaternary ammonium compound

If R is an alkyl group of 6-18 carbon atoms having distinct affinity for wool -mixed with non-ionic detergents to obtain a moth-proofing composition

Wool Protection

D-empethrin - protects woollen fabric against damage by pests such as moth & beetle

Insect repellent N,N diethyl diphenyl acetamide(DEPA) protection against larvae of carpet beetle clothes moth through impregnation of wool fabic - DEPA at 5% level provided protection to the fabric from the larvae

30 species of moth larvae and 15 species of beetle larvae - digest keratin.

Application done in the dyebath by exlmust methods - after continuous scouring process, melange printing, water proofing and bleaching processes - by exhaust techniques from organic solvents.

Pre- requisites of suitable compounds - good and rapid biological action - compatibility of other finishes like antimicrobial - in dyeing and with other auxiliaries - no alteration of the appearance, physical, chemical and physiological properties of textiles - ecologically acceptable - e.g. low warm-blood toxicity, biologically degradable, etc.

73% of all moth proofing finishes - applied by exhaustion from the dyebath and about 13% in wool scouring from aqueous solution

Estimation of moth and beetle proofing - done by biological tests or chemical analysis, which is based on gas chromatography.

Wool Protection

Insect Repellency for different textiles

Insect-resisting agents based on pyrethroid & permethrin - have little affinity for wool when applied from a pure solvent. A study of fastness properties of these finishes applied by dip-extract technique - indicates that water added to the processing bath as co-solvent significantly improves the fastness

Mechanism for uptake of water insoluble mothproofing agent by wool is analogous to that of a disperse dye.

An aqueous solution of sodium sulphite - a suitable system to solubilise and promote exhaustion of the mothproofing agent on wool - the system also confers shrink-resist properties on wool

Synthetic fabrics – exposure to pesticides - better degradation resistance than natural fibres – exhibit higher wicking level than cotton

Insect Repellency for different textiles

Rapid transport of pesticide solution from fabrics - characterised by slight degradation(reduction of tensile strength) and very high rate of drop absorbency, compared with high wicking level. The lowest level of absorbency and wicking level are found in 65/35 polyester/cotton blend fabric with and easy care-fabrics

Effects of Insect Repellent finish

Minimum discoloration - observed after one or two insecticidal applications- when applied at higher concentrations, they caused greater dye degradtionand fading during exposure and high temperature/humidity

Carbamate insecticides cause minimal degradation in dyed and undyed specimen

Pyrethrin containing products - cause significant discoloration on undyed nylon and acid/disperse blue dyes in both exposure conditions

Hot water cleaning - accelerates insecticide discoloration of nylon carpeting. The dyes vary in sensitivity to the insecticidal products.

The same blue acid and disperse dyes are more adversely affected by pyrethrin and pyrethroid insecticides - red dyes are more sensitive to organophophates resulting in significant increase in fading during exposure

Mosquito Repellent Finishes : A vital breakthrough

Basically mosquito repelling textiles are the ones which have a character of repelling mosquitoes.

This feature was developed as a need in sense of protection from the mosquitoes in the areas which are habitats of the mosquitoes and are prone to disease like malaria.

To impart this feature, the textile material is given an anti mosquito finish with an agent.

This agent is capable of being used on textiles without spoiling their characteristics and has good washing fastness.

Objectives

On an overall basis, the need is for finishing textile products to protect against mosquito-transmitted viral infections such as Malaria, West Nile fever and Japanese encephalitis, etc.

Note :

Daiwa Chemical was the first in Japan to introduce a mosquito repellent called Kaknock, a medicated cosmetic agent which repels mosquitoes by direct application on the skin in 1947.

Applications

The mosquito repellant textiles can be used in apparels and also in home textile industry.

In the mosquito prone areas these textiles find their applications in wall coverings & tents.

The insect repelling textiles find their applications in apparels and home textiles too.

Apart from these applications these textile materials can also be used for manufacturing bags used for storing eatables, textiles, perishable goods and all other goods prone to damage by insects.

Further DevelopmentsAninsen CLC-3600

After the experience with Kaknock, Daiwa Chemical put Aninsen CLC-3600, on textiles.

Capable of being used without spoiling their characteristics and has good washing fastness

Finishing textiles with Aninsen CLC-3600 keeps mosquitoes away from the processed surface before blood sucking behavior.

Characteristics: Milky white liquid

Ionicity: Anionic

Oral toxicity (rat): LD50 > 5,000mg/kg

Component: Toluamide compounds

Features: Repels mosquitoes by processing of fiber using organic compounds.Treatment by dipping and spraying in general.Main use in garments (outdoor wear, summer kimono etc.)Applicable materials are cotton, polyester and their blends

MECHANISM OF REPELLENT ACTION

Action of repellent agent of mosquitoes - divided into 2 types - actions to repel insects by acting on the olfactory and tactile senses

Action of repellent on sense of smell - transpiration repelling - keeps insects away without letting them touch a surface processed with the repellent agent

Mosquitoes - use warm and humid convection rising from the human body as a guide for contacting humans - sense an increase in atmospheric CO2 concentration

Repellent molecules - block insects’ humidity sensory holes - makes humans inaccessible to insects by inhibiting the function of sensing moisture

Action of repellent stimulating sense of touch - direct contact repelling

Drives insects off the processed surface before blood sucking even after touching the surface

Repellent substances - work on insects’ peripheral nervous systems when contact is made

Causes a confused state and inhibition under sub-lethal doses before knockdown and lethal action

Microencapsulation - clothing manufacturers are using to add value to their ranges

This technology - relatively new to the textile and apparel industry

Innovative technology - use of micro capsules which act as tiny containers of solids or liquids

These containers release their core contents under controlled conditions to suit a specific purpose.

MECHANISM OF REPELLENT ACTION

Imparting finishes on textile materials

ImpartingTechnique

Type of fabric Repellent type Outcome

Pad dry cure Scoured. Bleached & dyed, 100% cotton rib knitted

Microencapsulation Mosquito repellency

Rinse cycle laundry additives

Various DEET Mosquito repellency

Dipping Cotton Permethrin Mosquito repellency

Aerosols Cotton Microencapsulation DEET

Mosquito repellency

Rinse cycle laundry additives

Non-woven fabric Pyrethrum Mosquito repellency

Imparting finishes on textile materials

ImpartingTechnique

Type of fabric Repellent type Outcome

Impregnation Battle field uniform : 65%/35% Cotton/Polyester

KBR 3023 Mosquito mortality

Attached by resin solution

Natural & synthetic fabric

Microencapsulation Permethrin

Mosquito repellency

Pad dry cure Blend of natural & synthetic fabric

Permethrin Mosquito knockdown

Pad dry cure 100% polyester Microencapsulation Mosquito repellency

Direct coating Bleached cotton Microencapsulation Mosquito landing & repellency

Finish Assessment : Cone test

Test – doesn’t involve human participants - bait to lure the mosquitoes come from fabric - advantage of this method

The use of artificial blood or animal blood as bait in order to attract host seeking mosquitoes.

The mosquitoes might spend more time resting on the cone than on the treated surface during the 3 min exposition. The 3-min exposure test is carried out at temperature of 27 °C.

The standard WHO plastic cone is placed on top of the treated surface of the sample and secured using a masking tape.

Finish Assessment : Cage Test

Cage test - assesses viability of repelling substance against mosquitoes for lotions, cream, etc.

Designed to observe the mosquito landing on the untreated and treated fabric in the cage.

Advantage - provides real situation of probing and biting of the mosquito to the human.

Drawback - human participation

The mosquitoes used in the test need to be free from pathogen as the human subject involved in the test must have the assurance that the test will not harm them.

The cage measurement is according to WHO guideline for efficacy testing of mosquito repellents for human skin.

Fig: Cage test

References

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Pesticides : Advances in Research & Application. 2013 edition. Page 750. Scholarly Editions. Retrieved from : Google Books

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Paul R. Functional finishes for textiles. Page 334. Elsevier Publishers. Retrieved from : Google Books

Kadolph. Textiles. Page 374. Pearson Education India. Retrieved from : Google Books

Debboun M. & Frances S. P. Insect Repellents. Page 265. CRC Press Retrieved from : Google Books

Malik T. & Kumar A. Mosquito Repellent Textiles. Shri Vaishnav Institute of Technology & Science, Indore. Retrieved from : TechnicalTextile.net

Anuar A.A. & Yusof N. Methods of imparting mosquito repellent agents. Fashion & Textiles. Retrieved from : Link.Springer.com

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