FIELD OF THE INVENTION

The present invention broadly relates to the treated textile fabric. More particularly, the present invention relates to an antimicrobial non-woven textile having antimicrobial longevity, biodegradability and eco-friendly. In particular, the invention relates to a biodegradable and antimicrobial multi-layered textile material coated with nano-sized anodic metal colloids to provide a neutralising effect and a method for producing the same.

BACKGROUND OF THE INVENTION

[001] The transmission of any infectious microorganisms is usually controlled with the use of safety garments for health care personnel that can minimize the possibility of passage of such microbes/pathogens from non-sterile to sterile areas. Such garments are made of textile material that is used for making mask, gown, sheets, gloves, headwear, drapes and other related items for its usage at various places like hospitals, home, offices, hotels etc. The relevancy of such garments has become more prominent in view of the emergence and detection of the pandemics such asCovid-19 virus and other related disease.

[002] Most of the existing protective garments such as masks, gloves, sheets and drapes are made up of synthetic fibres polymer such as nonwoven polypropylene, Polyurethane, polyacrylonitrile, polystyrene, polycarbonate, polyethylene, or polyester or blends thereof. Moreover, such garments are mostly disposable and can be used for a limited time span thus, adding to the financial burden during the current crisis. Nevertheless, protective masks like N95 or similar grade masks are expensive and have higher overall usage cost. Also, use of such plastic-based synthetic fibres needs to be disposed after every single use and, hence increases the hazardous clinical waste in the environment as they are non-degradable in nature, creating massive land fill problems of such material disposal. [003] Comfort is another important characteristic of gowns, face masks and other garments intended to limit the potential risk of cross-contamination. The existing face mask causes difficulty in breathing or suffocation due to the dampness and heat generated thus resulting in anxiety or discomfort or unconsciousness in the users.

[004] Briefly, N95 MASK or other similar masks is tested as best option as compared to fabric mask. However, all N95 and related masks are mentioned as merely as respirators with PFE 95% to prevent Aerosols and particulates of size 0.30 micron and above. It should be noted that the current virus, being smaller than 0.12 micron, can easily pass through the N95 mask and infect the wearer.

[005] Therefore, in light of the above shortcomings with the existing materials of synthetic fibres, there is a dire need to develop a biodegradable and neutralising textile material which can be available at affordable price, efficient in preventing and neutralising microbial transmission, comfortable for use and suitable for recycling purpose and eco-friendly in nature. The textile material should be able to effectively filter and neutralise a large array of microbes/pathogens including bacteria, viruses, yeast, fungi, molds and protozoa.

OBJECT OF THE INVENTION

[006] An object of the present invention pertains to a method of preparing a nano metal coated multi-layered non-woven fabric to create a virus and bacteria neutralizing effect against microbes/pathogens.

[007] Another object of the present invention is to provide a novel and improved nano metal coated multi-layered non-woven fabric having high filtration efficiency and neutralising effect.

[008] Another object of the present invention is to provide a coated textile material which is cost-effective, non-toxic, biodegradable, breathable and capable of neutralising microbes/pathogens.

SUMMARY OF THE INVENTION [009] The present invention is described hereinafter by various embodiments. This invention may, however, be embodied in many different forms, should not be construed as limited to the embodiments set forth herein. Rather, the embodiments are provided with the intent of imparting clarity pertaining to the scope of the invention to those skilled in the art.

[0010] In an embodiment, the present invention relates to a method of preparing a nano metal coated multi-layered non-woven fabric comprising the steps of: i. Collecting and processing biodegradable nonwoven fabric; ii. preparing a coating paste having nano-sized anodic metal colloids, binder of organic ingredients and water; wherein 100 kg water comprises 0.05 -3.00 kg of metal colloid and 5-10 kg of binder solution; iii. applying the coating paste obtained from step (ii) on the outer surface of top and bottom non-woven fabric; iv. dehydrating and drying the coating paste solution in a curing chamber at the temperature ranging from 120°C to 150°C for the time ranging from 40-60 seconds at a temperature of to obtain a coating film; v. obtaining a multi-layered biodegradable and antimicrobial nonwoven fabric.

DETAILED DESCRIPTION OF THE INVENTION

[0011] Various modifications to these embodiments are apparent to those skilled in the art from the description and the accompanying drawings. The principles associated with the various embodiments described herein may be applied to other embodiments. Therefore, the description is not intended to be limited to the embodiments shown with the accompanying drawings but is to provide broadest scope consistent with the principles and the novel as well as inventive features disclosed or suggested herein. Accordingly, the invention is anticipated to hold on to all other alternatives, modifications, and variations that fall within the scope of the present invention. [0012] The invention discloses a novel and improved multi-layered antimicrobial and biodegradable textile material coated with nano-sized anodic metal colloids which may be capable of filtering, neutralising and protecting against large array of microbes/pathogens and other pathogens including but not limited to bacteria, virus, yeast, fungi, molds and protozoa, according to the embodiments of the invention. The textile material coated with nano-sized anodic metal colloids may have a neutralising effect against the microbes/pathogens and other pathogens gets deposited on the surface of material and it may have high filtration efficiency, at least 90 percent filtration efficiency and can go upto 99.99% against oil-based or non-oil-based particles, depending on the number of layers and coatings used in the textile.

[0013] Silver ions are microbial and bind irreversibly with the electron transport components. They suppress the respiratory enzyme and interfere with the DNA function, thus, not only destroying virus & bacteria, but also prevent proliferation and effectively give a long duration microbial protection. Hence, use of silver ions as a metal-colloids in the fabric disclosed in the present invention leads to the rupture of the spiked envelope of virus, rendering it neutralised and ineffective.

[0014] The textile material may be utilized in any suitable application, including, without limitation, face masks, gloves, bedding, laboratory coats, and medical robes, wiping cloths, towels, rugs, floor mats, drapery, textile bags, vehicle covers, and the like that can be easily used by the healthcare professionals as well as the public. The coated textile material of the present invention is cost-effective, non-toxic, biodegradable, and breathable and capable of neutralising microbes/pathogens.

[0015] Such textile material may be of any standard construction in the form of non-woven form. The nonwoven fabric may be used in forms like spunbond or meltblown or spunlace, multi layered SMS, SSMMS, SMMS or any combination [0016] In a preferred embodiment, the present invention relates to a method of preparing a nano metal coated multi-layered non-woven fabric comprising the steps of: i. Collecting and processing nonwoven fabric; ii. preparing a coating paste having nano-sized anodic metal colloids, binder of organic ingredients and water; wherein to 90-99% litres of water 0.100-0.300 kg of silver metal colloid and 1.00-10.00 kg of binder was added to obtain 100 litres of the coating paste solution; iii. applying the coating paste obtained from step (ii) on the outer surface of top and bottom non-woven fabric; iv. dehydrating and drying the coating paste in a curing chamber at the temperature ranging from 120°C to 150°C for the time ranging from 40-60 seconds at a temperature of to obtain a coating film; v. obtaining a multi-layered biodegradable and antimicrobial nonwoven fabric.

In yet another embodiment, said nonwoven fabric is selected from a group consisting of, but not limited to, polylactic acid (PLA), polypropylene, polyester, cotton, viscose and a combination thereof, and a water miscible binder dispersed in a sulfonated medium wherein, the top and bottom layer of the textile is coated or/and padded with nano-sized anodic metal colloids.

In yet another embodiment, the diameter of said fibres are in the range of diameter in the range of 8-10 microns.

In yet another embodiment, said metal colloid is selected from, but not limited to, silver and/or zinc and/or copper.

In yet another embodiment, said metal colloid is selected from silver nanoparticles.

In yet another embodiment, the size of the anodic metal colloids ranges from 30- 50 nm.

In yet another embodiment, said water miscible binders comprising organic ingredients are selected from a group consisting of biodegradable binders based on starch, chitosan, collagen, gelatin, albumin, lignins, carreganen, guar gum, pectins, soya, casein, whey, sulfonated polyester and a combination thereof. In another embodiment, the present invention relates to a nano metal coated multilayered non-woven fabric comprising nonwoven fabric selected from, but not limited to, polylactic acid, PLA, polypropylene, polyester, cotton, viscose and a combination thereof, and wherein, the top and bottom layer of the textile is coated or/and padded with nano-sized anodic metal colloids.

In yet another embodiment, said anodic metal is selected from nano-silver.

In yet another embodiment, the density of said nonwoven material is in the range of 10-200 grams per square meter (gsm).

In yet another embodiment, said non-woven coated fabric exhibits 91.64%, 94.84% and 96.18% reduction of virus in 30 Seconds, 3 minutes & 30 minutes respectively.

In yet another embodiment, said antimicrobial fabric is antimicrobial, biodegradable and eco-friendly.

[0017] The one or more layers in the said textile material are made of biodegradable, non-woven fibres of polylactic acid. It is pertinent to note that number of layers in the textile material may increase or decrease, in accordance to the use of the textile material. For instance, if the said fabric is used in making of any protective garment, then, three or more layers may be incorporated, for instance, in surgical masks, N95, N99, N100, R95, P95, P99, Pl 00 or similar grade mask or protective material to provide at least 90 percent filtration efficiency against oil-based or non-oil -based particles to the user. Any other resin or additive may be added to the fabric of the present invention, as long as it biodegradable in nature and does not interfere with the advantageous properties of the fabric.

EXAMPLES:

The below examples are provided in a stepwise manner.

Example 1: Collection and coating of the fabric: [0018] Polylactic acid is derived from corn starch and other bio-based compostable natural materials. Polylactic acid (PLA) non-woven fabric is used in the present invention is procured from Lakshya Nano Technologies. Non-woven PLA of 40 GSM was collected and about 50 Kgs of the fabric material was used for further experiment. The PLA was selected as it is compostable and breaks down and starts decomposing when mixed in soil by absorbing moisture and microorganisms to make it a bio waste thus, eco-friendly in nature. The nonwoven fabric was prepared by spunbond or meltblown or spunlace process as disclosed in the literature (Reference) using polylactic acid fibres having diameter in the range of 8-10 microns. It is to be noted that the polylactic acid non-woven fabric used in the present invention was prepared without addition of any chemical agents. The textile material used in the present invention have the density in the range of 10- 200 gsm, hence, economical, lightweight and comfortable to the users with respect to breathing and other discomfort. The textile materials may also include polypropylene, Cotton, Viscose rayon, Polyester by padding or coating process.

Example 2: Process of preparing the coating paste and solution for padding: [0019] The textile material of the present invention imparts an antimicrobial and neutralizing effect which is derived from the coating present on the outer surface of the top and bottom layer of the fabric with nano-sized anodic metal colloids. The silver ion and/or nano silver was used as anodic metals while performing the present invention, the mean particle size in the range of 30-50 nm. However, other metal colloids such as zinc and/or copper may also be used, where the nano-sized anodic metal colloids may have the mean particle size in the range of 20-80 nm. In order to get better results, a coating paste having nano-sized anodic metal colloids was prepared by mixing nano-sized anodic metal colloids, binder of organic ingredients and water. Briefly, about 1 kg nano silver colloid and 10 kg of organic binder was procured from FX Pigments.

[0020] To prepare the padding solution, initially 44.70 litres of distilled water was poured into a 200 litres capacity stainless steel container. Next 50 litres of distilled water, 5.00 kg of binder and 0.3 Kg of Nano Silver Colloid was poured into their respective dispensers (having flow control valves) and allowed to drop slowly into the 200-liter stainless steel vessel. The mixture was stirred by a Rotor Blade at Low rpm of 90 to 100. The mixing process was completed in about 10 minutes under temperature between 30 to 35 degrees Celsius and controlled atmosphere of dry air. Further, about 100 litres of Padding Solution was prepared and poured into 10 litres plastic carboys for storage. The resultant padding solution having composition of nano silver - 0.30 %, Binder - 5.00 %, water - 94.7% was achieved.

[0021] The initial step of making the above-mentioned fabric material may include one or more layer of nonwoven fabric made of polylactic acid (PLA) fibres. The next step may require preparation of a coating paste/solution having nano-sized anodic metal colloids, biodegradable binder and water present in the ratio of 0.30: 5.00: 94.70. It is to be noted that the mean particle size of silver colloids may range in 30-50 nm and the amount of silver used for coating the textile material may be present in the range of 3500 ppm to 4500 ppm having viscosity (at a temperature of 24°C) in the range of 8 to 12 cps and specific gravity in the range of 0.9 to 1.2. Such parameters help in providing a neutralising effect against the microbes/pathogens that are deposited on the surface of the fabric material.

[0022] The binder used for making the coating paste may be water miscible and biodegradable in nature. It may comprise of organic ingredients and needs to be dispersed in sulfonated medium. In the subsequent step, the coating paste may be homogenously applied on the outer surface of both the top and bottom fabric layers of the textile material which is further dehydrated and dried in a curing chamber for 40-50 seconds at a temperature of 120°C to 150°C to obtain a coating film. During this step, water evaporates from the paste resulting in an even homogeneous coating of nano-sized metal colloids on the fabric material.

Example 3: Nonwoven fabric coating and/or padding process

[0023] The fabric was passed through the coating solution which leads to the absorption of the solution by the fabric upto 30%. The excess content was squeezed out by the pressure rollers, leaving remnants on both sides. Further, the water from the semi wet fabric was evaporated by passing through the drying chambers which resulted into a very thin and fine film of nano-silver on both the sides, thus giving a 3 ply non-woven fabric as AgNp/ PLA non-woven/ AgNp.

[0024] Briefly, the PLA nonwoven fabric was mounted onto a feed delivery stand having ball bearings to avoid any pulling stress on to the non-woven (else nonwoven will rupture). The Nonwoven Fabric was passed through padding trough in which 100 litres of padding solution was filled. Excess solution was removed from the non-woven fabric by passing it through squeeze rubber coated roller. The non- woven fabric was clamped from the sides, straightened & fed into the drying chamber. In order to avoid any damage to non-woven fabric, it was under fed by 1 % warp wise and width gradually reduced by 1 % to get a stable coated fabric at the exit delivery point. The water content absorbed during padding gets evaporated when non-woven fabric was passed through the 27-meter-long drier chamber at 120 - 130 degree Celsius at 36 meters/ minute delivery speed. At exit point the dry nano silver coated PLA non-woven fabric was wound onto a semi positive take up roller.

[0025] Maximum care was taken to ensure that non-woven fabric is not distorted, ruptured, singed or damaged. Below experiments were performed at different delivery speed: -

1) 20meters/min - resulted into a very heavy deposit of final gsm = 50/52

2) 48meters/min - resulted into a lower deposit of final gsm = 42/43

3) Final at 36meters/min - resulted into desired final gsm = 44.5/45.5

. average 45 gsm

Final coated PLA non-woven fabric achieved displayed 45 gsm . i.e having average 5.0 gsm of nano silver and binder, (of which final deposit of 0.28 gsm of nano silver and 4.72 gsm of binder was achieved on the PLA non-woven fabric ). [0026] Hence, the present invention includes a uniform coating like a film on the outer surface of top and bottom layer of the fabric with nano-sized silver colloids to neutralise the microbes/pathogens which comes in contact with the fabric. Such coating may result in a three-layered fabric wherein, the nonwoven polylactic acid fabric is sandwiched between the homogeneous and uniformly spread films comprising active nano-sized silver colloids. The presence of nano-sized silver colloids in the coating creates a multi-dimensional positively charged surface area on either side of the fabric, which attracts and pulls the negatively charged microbes/pathogens, preferably virus; neutralizing and preventing the passage of microbes/pathogens through the fabric and effectively rendering the microbes/pathogens ineffective. Also, the small sized viruses are in a brownian motion and get attracted to the electrostatically charged area on either side of the nano silver quoted fabric thus, effectively neutralising the microbes/pathogens including the viruses deposited on its surface. The advantage of using the anodic metals for coating the fabric, as it does not induce resistance in the microorganisms and also helps to attract the microbes/pathogens due to electrostatically charged fabric material. Thus, the antimicrobial fabric of the present invention does not lose the antimicrobial strength over time, and the antimicrobial effects are long lasting. In addition, the coating film on either side of the textile material will ensure reduction of micro pores in the fabric, thus resulting in an overall antimicrobial, breathable and biodegradable textile material for various applications

Example 4: BEE (Bacterial filtration efficiency)

[0027] The BFE of the filter devices was measured as described by the ASTM F2101 method. Penetration was measured using the bacteria S. aureus as the challenge organism. A suspension of S. aureus was aerosolized using a nebulizer to give a challenge level of 3000 Minimum colony-forming units (CFU) per test as specified by the ASTM F2101 standard. The bacterial aerosol is a water droplet containing the bacteria and not an individual bacterial particle. The particles were not charge neutralized for testing. The test samples were preconditioned for 4 hr at 21±3°C and 85±5% RH, prior to testing. The aerosol sample was drawn through a test sample clamped into the top of a 6-stage Andersen sampler with agar plates for collection of the bacteria particles at a flow rate of 28.3 L/min for 1 min. The design of 6-stage Biological sampler is based on the human respiratory tract, where all airborne particles greater than 0.65 pm are classified aerodynamically. The flow rate of 28.3 L/min is similar to human breathing flow rate to obtain deposition of particles in different stages of the sampler. A positive control without a test filter sample clamped into the system was used to determine the number of viable particles being used in each test. A negative control with no bacteria in the airstream was performed to determine the background challenge in the glass aerosol chamber prior to testing. In case of contamination, the testing system was cleaned thoroughly to reduce negative control CFU. The residual negative control (<1%) was subtracted from the test sample CFU. The positive control result was used to obtain the MPS of the test aerosol. The MPS was calculated from the particle sizes (P1-P6) and respective CFU counts (C1-C6) in the 6-stage impactor.

BFE%= (Positive control CFU - Test sample CFU) xlOO/ Positive control CFU BFE results range from 1-99.9% as these values are the low (<1) and high (>99.9) detection limits which are based on the test parameters used and how the calculations are performed.

Example 5: PEE (Particulate filtration efficiency) Filtration Efficiency

[0028] Filter penetration for all devices was measured using the NIOSH NaCl aerosol method employed for certification of particulate respirators using an Automated Filter Tester. The samples were pre-conditioned at 85 ± 5% relative humidity and 38 ± 2.5°C for 25 ± 1 hr prior to measuring filter penetration. .A 2% (wt/vol) NaCl solution was aerosolized, charge neutralized and then passed through the convex side of a test sample properly sealed and placed into a filter holder. The particle size ranges from 0.022-0.259 pm with a count median diameter of 0.075 ± 0.020 pm. The concentrations of NaCl aerosol upstream and downstream of the sample were measured at 85 L/min flow rate. The full NIOSH certification test typically takes approximately 90-100 min to as shown below:

Penetration (%) = Particle concentration downstream x 100/ Particle concentration upstream

Penetration of each test sample was measured for 5 min or more time until maximum penetration was reached. For convenience and efficiency, doing the full loading test as done by NIOSH according to 42 CFR Part 84 during certification testing was not done in these experiments. From the percentage penetration, the efficiency was calculated as shown below:

Efficiency (%) = (100 - % Penetration)

Example 6: Evaluation of Antimicrobial Activity

[0029] In order to evaluate the antimicrobial activity of the claimed fabric, Test and control fabrics were cut into appropriately sized swatches of 50 mm diameter and stacked. The numbers of swatches taken were 2 in order to absorb the entire liquid inoculum of 0.5 ml quantity. Stock virus was standardized to prepare a test inoculum and test and control materials were inoculated with the test virus, and incubated in a humid environment at 350C temperature for the 30 Seconds, 3 minutes & 30 minutes contact time. The viral concentration was determined at “Time Zero” to verify the target inoculums using plaque assay techniques. Assay plates were further incubated for 48 hours for the virus-host cell system. After the incubation period, following neutralization, the carrier suspensions were quantified to determine the levels of infectious virus survived and the assay was scored for titre of test virus. Test sample labelled as nonwoven fabric as claimed in the present invention showed 91.64%, 94.84% and 96.18% reduction of Virus in 30 Seconds, 3 minutes & 30 minutes respectively when analysed as per AATCC 100 - 2012 test Method using MS2 Bacteriophage as surrogate virus (Table 1).

Table 1: Evaluation of Antimicrobial Activity of Fabric:

EXAMPLE 7: Determination of antiviral activity against SARS-Cov2

[0030] Due to the individual sensitivities, the results of one test virus cannot be transposed to the other virus. This test method was used for the determination of the antiviral activity of the textile product against specified Enveloped and nonenveloped viruses, virus & host cells used in testing were selected from Influenza A virus H3N2 ATCC VR-1679 Influenza A virus H1N1 ATCC VR-1469 Host: MDCK cell ATCC CCL-34

Sterile Test specimen and Control specimen weighing 0.40g of dimension 20mm x 20mm were used for testing. Test was carried out in Triplicates. Virus suspension having density of 1.50 x 10 ⁸ PFU / ml was used for test. Aseptically 0.2ml of virus suspension was inoculated at several points on Test and Control specimens. At 0 hours, Control specimens were terminated to obtain baseline virus titre by adding 20ml SCDLP medium. This wash out solution was used for virus titre determination. Test and Control specimen inoculated with virus suspension were Incubated at 37° c for 2hrs in CO2 incubator. At the end of 2 hours, Test and Control specimens were terminated using 20ml SCDLP medium. The wash out solution so obtained was used for virus titre determination.

TCID50 method

One day before titration of virus, 96 well plates with MDCK cells were prepared. The wash out solution obtained after contact time was serially diluted using 96 U well plate. An aliquote measuring 25 ul were seeded onto washed MDCK host cells. The plates were incubated for one hour at 37°C. For virus penetration, infectious medium was added to all the wells containing virus. Plates were then incubated for 37° C for 7 days. After incubation, plates were examined for CPE which was confirmed by Methylene blue staining and or Haemagglutination method. Conditions for verification of this test

Verification of cytotoxicity by cell sensitivity to virus and the inactivation of antiviral activity was also verified Log TCZD ₅ o/ml of control- log of TCZD ₅ o/ml of test specimen was expected to be < 0.5.

Viral titre Calculations:

Score the titre was by determining the last dilution with positive hemagglutination score. The no of positive wells from the last dilution (no. of the and of 3). From this score TCZD ₅ o/25pl was calculate by Behren’s and Karber method.

Calculation of antiviral activity value

Mv = Log (Va/Vc) = Log (Va) - Log (Vc)

Where,

Mv = antiviral activity value

Log (Va) = is the common logarithm average of 3 infectivity titre value immediate after inoculation of the control specimen.

Log (Vc) = is the common logarithm average of 3 infectivity titre value after 2hrs contact with the antiviral fabric specimen.

The fibre obtained was found to be 100% protective against SARS-Cov2. It is worth noting that SARS-Cov2 belongs to the envelope virus family common to H1N1 and H3N2, which are known to have even smaller than SARS cov in size. The fabric is capable enough to neutralize the smallest of the small of viruses.

EXAMPLE 8: Evaluation of anti-viral activity using non-enveloped MS2 Bacteriophage virus by quantitative method

The method provides quantitative measure for the degree of antiviral activity. This method is important for evaluation of virucidal activity of a finished fabric. MS2 Bacteriophage is used as screening virus. Sterile Test specimen swatches of diameter 4.8 cm ± 0.1 cm discs weighing 0.75 gram were stacked and placed in 250 ml wide mouth sterile bottle with a screw cap. MS2 Bacteriophage suspension having 1-5 x 10 ⁶ PFU/ ml was prepared. 0.5 ml of this suspension was inoculated on to the Test specimen. A standard control specimen (Negative control) with no antiviral activity was also inoculated with 0.5 ml MS2 Bacteriophage suspension. At zero hours, Test as well as control specimen were terminated to estimate count of MS2 Bacteriophage inoculated on fabric at the start of experiment.

For estimating antiviral activity, Test and Control specimen were incubated at 35°C for 24 hours. At the end of incubation period, 20 ml of sterile neutralizing solution was added. The bottles were vortexed to elute the virus into the suspension. This suspension was serially diluted in phosphate buffer. Aliqoute of 1 mL was then transferred to test tubes containing 100 pL host E. coh. vortex for 30 seconds and allowed 5minute contact for virus adsorption. To the above mixture, 4 mL of molten, tempered 1 % Trypticase soya agar (TSA) was added and mixed for homogeneity and then poured evenly onto the pre-prepared sterile TSA plates and rotated gently to make uniform layer. Plates were allowd to solidify and incubated at 35° C for 18-24 hours. After the incubation period, viral plaques were counted.

Percent reduction of virus was calculated using the following formulas: 100 (B-A)/B = R

Where R = % reduction

A = the number of bacteriiophage recovered from the inoculated treated test

Specimen swatches in the bottle incubated over the desired contact period.

B = the number of bacteriiophage recovered from the inoculated treated test

Specimen swatches in the bottle immediately after inoculation EXAMPLE 9: Evaluation of antifungal activity using quantitative method [0031] The method provides quantitative measure for the degree of antifungal activity of a finished fabric. Mucor spp. Was used to evaluate antifungal activity Sterile Test specimen swatches of diameter 4.8 cm ± 0.1 cm discs weighing 1 gram were stacked and placed in 250 ml wide mouth sterile bottle with a screw cap. Standardized mucor suspension having 1-5 x 10 ⁶ CFU/ ml was prepared. Accurately, 1 ml of this suspension was inoculated on to the Test specimen. A standard control specimen (Negative control) with no antifungal activity was also inoculated with 1 ml of Mucor suspension. At zero hours, Test as well as control specimen were terminated to estimate count of Mucor inoculated on fabric at the start of experiment.

For estimating antifungal activity, Test and Control specimen were incubated at 28°C for 48 hours. At the end of incubation period, 100 ml of sterile neutralizing solution was added. The bottles were vortexed to elute the spores into the suspension. This suspension was serially diluted in phosphate buffer. Standard plate count method was followed using Potato Dextrose agar. Plates were incubated at 28° C for 48 hours.

Percent reduction of Fungal spores was calculated using the following formulas: 100 (B-A)/B = R

Where R = % reduction

A = the number of spores recovered from the inoculated treated test

Specimen swatches in the bottle incubated over the desired contact period.

B = the number of spores recovered from the inoculated treated test

Specimen swatches in the bottle immediately after inoculation

[0032] The features, structures, or characteristics of the invention described throughout this specification may be combined in any suitable manner in one or more embodiments. For example, reference throughout this specification to “certain embodiments,” “some embodiments,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in certain embodiments,” “in some embodiment,” “in other embodiments,” or similar language throughout this specification do not necessarily all refer to the same group of embodiments and the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0033] It should be noted that reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussion of the features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment.

[0034] Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention.

[0035] One having ordinary skill in the art will readily understand that the invention as discussed above may be practiced with steps in a different order, and/or with hardware elements in configurations which are different than those which are disclosed. Therefore, although the invention has been described based upon these preferred embodiments, it would be apparent to those of skill in the art that certain modifications, variations, and alternative constructions would be apparent, while remaining within the spirit and scope of the invention. In order to determine the metes and bounds of the invention, therefore, reference should be made to the appended claims.

[0036] ADVANTAGES OF THE PRESENT INVENTION

• The fabric material of the present invention is self-compostable and biodegradable having short compostable time period and non-toxic thus, environment friendly in nature.

• As the fabric is eco-friendly, compostable and biodegradable, it eliminates the landfill problems created due to the hazardous non-biodegradable materials currently being used.

• The fabric material uses natural PLA fibre extruded from polylactic acid derived from com starch for making various protective garments and products.

• The fabric material has good air permeability improving the inhaling and exhaling properties of the fabric.

• The fabric material is hypo allergenic (skin friendly)

• The presence of nano-sized metal colloids creates a multi-dimensional positive field to protect the users from viruses, bacteria, fungi, molds and protozoa.

• The fabric material is soft, easy to make, effective and economical for the users as it solves the land fill problems created due to hazardous nonbiodegradable materials and, thus reducing the overall cost in comparison to the disposable synthetic fabrics.

• The fabric material can be used on a largescale basis during any pandemic outbreak such as Coronavirus (Covid- 19) outbreak.

• The fabric material being bio-degradable can be recycled as these are all disposable single use materials.

• The layers in the fabric may be increased or decreased to provide at least 90 percent filtration efficiency against oil-based or non-oil-based particles to the users. • The fabric material is very lightweight hence comfortable to the users.