Title of Invention

"A PROCESS FOR INDUCTING ANTI-MICROBIAL AND ANTI CREASE PROPERTY IN TEXTILE MATERIAL"

Abstract

The invention discloses the process to induct anti-microbial and anti crease property in textile material by exposing the textile material intended to get inducted with the antimicrobial and anticrease property to a composition comprising crosslinking agent, acid catalyst, and catalyst activator such as herein described followed by exposing to the solution of neem extract (active antimicrobial agent) containing coreactant to crosslinking agent in such a manner to get 100 to 110 % wet expression on the material or 1.3 to 8.099% of neem extract or 0.1 to 1.15% of limonoid get inducted in the material, followed by drying and curing the material to get anti-microbial and anti crease property inducted textile material. The invention also claims the material having anti-microbial and anti crease property inducted in it.

Full Text

This invention relates to a process for inducting anti-microbial and anti crease property in textile material. FIELD OF INVENTION: The invention specifically, relates to a process that can induct anti-microbial and anti-crease properties in the textile material, including natural as well as their blends and fibres, by treating the said material with an agent capable of inducting these properties. Particularly, the invention provides a process that is economic, eco-friendly. More particularly, the process of this invention requires less power and time. Still more particularly, the process is capable of inducting the property that does not get affected by prolonged use and is capable of standing repeated washings. Additionally, the textile material obtained by the process disclosed and claimed in this invention has potential use as a dermal dressing material. The antimicrobial agent inducted/ integrated in the fabrics kills the cell wall of microbes when placed on infected area thereby curing the infection caused. BACKGROUND OF THE INVENTION: Textile material, in general, is susceptible to the attack by bacteria, mold, fungi, mildew, mites, pests and other microbes, which deteriorate the material thereby reducing the life of the material. This is more applicable to the material like carpet, upholstery that remains in use for several years and is required to be cleaned in place. Steam cleaning or other measures of cleaning, though are effective to remove dirt or stains, found ineffective to remove microbes that are harmful to the material and user. The bioactive finish to the fabric has in general two-fold function. One to protect the fabric from getting deteriorated due to microbial inhabitation and action as stated herein above and the other is to protect the wearer from the microbes for aesthetic, hygiene or medicinal reasons. It is well known that the staphylococcal organisms are associated with the dermal secretions like sweat that cause itiching and other health problems. The bioactive finish to the fabric through the acquired antimicrobial property helps in taking care of such problems. Relevant art known to the inventor include Patent No. WO 03071871. The patent under reference advocates introducing microcapsules containing vaporizable active substance having microbicidal property in the textile substrate. The substrate diffuses the membrane of the capsule and produces constant active substance concentration on the textile substrate. The active substance used is pest repellent extract from Neem. In accordance with Patent No. FR 2826380 also published as WO03002807, the microcapsules containing Neem oil are fixed on the textile material to impart acaricidal and microbicidal property to the said material. The capsules also optionally contain scents or deodorants. Japanese patent Application number 11-123022, teaches treating the washed coagulated yarn with chitosan, a natural anti-microbial agent, in production process. This treatment appears to be applicable only to acrylic fibres. EP 0863248 relates to a safe textile pesticide suitable for finishing textile at high temperatures. The pesticide is derived from Neem tree fruit extracts containing azadirachtin (I), surfactants and optionally other ancillaries in an aqueous formulation. According to this invention, about 100 to 30,000 ppm preferably 500 to 15,000 ppm Neem extract in terms of azadirachtin is applied on the substrate to impart desired property against infestation and eating damage by textile parasites. JP 2000355880 discloses knitted or woven fabric with anti-microbial property. The fabric with desired anti-microbial property is obtained by using a cellulosic yarn impregnated with at least a methylol-based resin, a cross-linking catalyst and a spinning oil agent using heat treatment. The heat treatment is carried out at a temperature of 110 C to 170 C for 0.5 to 10 minutes. Further, in accordance with the said invention the methylol-based resin is a condensate of an alkyleneurea, hydroxyethyleneurea, triazone, melamine or an alkyl carbide and formalin. WO03057950 describes topical treatment for carpets, upholstery etc. using stable emulsion in water of an anti-microbicidal compound preferably 'permethrin', (3-phenoxy methyl)methyl()cis-trans3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate. This solution is, generally, sprayed on the material or the material is immersed in the solution to be applied. Additionally, some synthetic anti-microbial products are commercially available. However, use of these products is often associated with problems such as skin allergies, environment (water, soil, air) pollution and impairing of ecosystem through side effect on non-targeted organisms. Further, it is likely to lead to lethal or non lethal accidents due to mishandling of such highly toxic substances, which necessitates very skilled personnel. T.L. Vigo has reported using inorganic anti-microbial agent based on magnesium hydroperoxide and related structures so as to make the agency environment friendly. As outlined above the existing methodologies involve inorganic anti-microbial agent, naturally occurring agent such as chitosan, permethrin, encapsulated neem oil or neem extract and methylol based resin in combination with cross linking agent and spinning oil agent. It may be noted that the microcapsules are fixed on the fabric and are not an integral part of the fabric thereby limiting the activity/efficiency. Further the active substance used has to be vaporizable and capable of diffusing through the membrane of the capsule. The heat treatment is conducted at high temperature, which results in deterioration of the fabric quality. Moreover all the methods address to the applicability of the technology to the fabric that is not cleaned regularly. Thus, none of these method teaches the protection offered to the wearer by retaining and sustaining the inducted property over a prolonged period even after repeated washing. The drawbacks of the synthetic anti-microbial agents have already been pointed out hereinabove. In general most of the methods impart the property to the substrate as against the process of the present invention inducts the property in the substrate. The inducted anti-microbial property helps in inhibiting, retarding, and or arresting growth of foulants for a long period. It also acts as microbicidal including mites, fungi, bacteria etc. The textile material obtained by the process disclosed and claimed in this invention also has a potential use as a dermal dressing material. The antimicrobial agent inducted/ integrated in the fabrics kills the cell wall of microbes when placed on infected area thereby curing the infection caused. Additionally, the anti-crease property is also imparted to the fabric, which enhances the economic value of the fabric. SUMMARY OF THE INVENTION: The main object of this invention is to provide a process for inducting anti-microbial and anti-crease property in the textile obviating the problems associated with the existing processes. Other object of this invention is to provide a process for producing bioactive finish to the fabric, which offers protection to the wearer from ill effects of microorganisms in addition to protecting the fabric from biodeterioration due to inhabitation of microorganisms. Another object of this invention is to provide a process that is economical, environment friendly, requires less time and power. It is a further object of this invention is to provide a process for producing textile material having acquired anti-microbial and added anti crease property. Another object of this invention is to provide a process for producing textile material with desired property that does not get affected by prolonged use and is capable of standing repeated washings. Yet another object of this invention is to provide a process that uses anti-microbial agent that is easily procured from abundantly available natural source, eco friendly and safe to the user. The above objects are achieved by padding fabric/yarn using two dip and two nip process with an aqueous solution containing desired anti-microbial agent in addition to other components followed by drying and curing at various wave frequencies exemplified by but not limiting to curing in a microwave at different powers. The present process ensures the cross linking of the compound with the substrate as herein after enumerated. The textile material includes the natural as well as their blends and yarns and the antimicrobial property also extends to acaricidal property and powers to fight other textile parasites. STATEMENT OF THE INVENTION: Accordingly the present invention provides a process for inducting anti-microbial and anti crease property in textile material and the material thus produced wherein the process comprising (i) exposing the textile material intended to get inducted with the antimicrobial and anticrease property to a composition comprising crosslinking agent, acid catalyst, and catalyst activator such as herein described followed by exposing to the solution of neem extract (active antimicrobial agent) containing coreactant to crosslinking agent in such a manner to get 100 to 110 % wet expression on the material or 1.3 to 8.099% of neem extract or 0.1 to 1.15% of limonoid get inducted in the material, (ii) drying and curing the material in a manner such as herein described to get antimicrobial and anti crease property inducted textile material. According to one of the embodiments of this invention the textile material used may be exemplified by cotton, cotton polyester blend fabric or yarn preferably fabric. Other embodiment of this invention is to provide a process wherein the exposing may be carried out by conventional two dip and two nip process by dipping the material in the said composition and removing excess composition twice to facilitate the composition to get absorbed in the material. Another embodiment of this invention is to provide a process wherein the crosslinking agent used may be such as Dimethlylol dihydroxy ethyleneurea (DMDHEU), glyoxal, polycarboxhc acids such as citric acid (CA) and BTCA preferably glyoxal and may be employed in the range of 2 to 15 % by wt. preferably 5% by wt o total composition. Yet other embodiment of this invention is to provide a process wherein the acid catalyst used used may be exemplified but not limiting to magnesium chloride, aluminum sulphate, sodium bisulphate or zirconium sulphate preferably aluminum sulphate when fabric to be treated is cotton, and may be added in the range of 0.1 to 8 % by wt. preferably 4 % by wt. of crosslinking agent. Yet another embodiment of this invention is to provide a process wherein the catalyst activator used may be such as α hydroxyl acid such as tartaric acid, glycolic acid, lactic acid, succinic acid preferably tartaric acid when catalyst is aluminum sulphate and may be employed in the range of 2 to 6% preferably 4% by wt. of crosslinking agent. Still other embodiment of this invention is to provide a process wherein the neem extract employed may be seed or bark extract. Still another embodiment of this invention is to provide a process wherein the coreactant to crosslinking agent used may be such as glycol having chain length of 2-8 carbon atoms exclusive of terminal hydroxyl groups, preferably ethylene glycol and added in equimolar quantities of crosslinking agent exemplified by glyoxal. Further the drying and curing may be effected at 1 GHz to 40 GHz employing microwave at power between 200 and 2000w for not exceeding 1 minute or is effected in conventional oven at a temperature ranging from 115°C to 125°C preferably at 120°C for up to 2 minutes. However please be noted that the drying in oven need to be preceded by curing. DETAILED DESCRIPTION: The neem extract was used as an anti-microbial agent since ages. The selection of neem is generally due to its unique proven medicinal property and abundant availability in the nature. Further, it's safety to environment and consumer is proven beyond doubt. However, it is the first time that the neem extract, which is a natural antimicrobial agent, in combination with other environmentally safe substances are integrated in the substrate such as textile fabric to induct anti-microbial and anti-crease property in the said substrate so as to protect the substrate/fabric as well as wearer from ill effects of infestation of microorganisms for an extended period. Additionally, the textile material obtained by the process disclosed and claimed in this invention has potential use as a dermal dressing material. The antimicrobial agent inducted/ integrated in the fabrics kills the cell wall of microbes when placed on infected area thereby curing the infection caused. Further, the process is simple and low cost and safe. The power and time requirement for the entire operation is also considerably reduced. Additionally, while inducting the property the loss in fabric strength is minimal. Though the description herein after is exemplified by cotton and polymix the process can be employed to other fabrics and thus need not limit the scope of the invention. Cotton and cotton polyester blend fabric were used for integration of neem active ingredients. The active ingredients of neem include limonoids. Azadirachtin, nimbin and salannin are the three major limonoids of neem. The solvent used for extraction is methanol. Generally, the characterization of neem extract is based on azadirachtin content in the extract. But it was found that azadirachtin is effective against pest and has no activity against bacteria. Therefore the extracts were characterized in terms of its three major active ingredients namely Azadirachtin, nimbin and salannin. Neem seed, bark and leaf extract were applied on to the fabric by using pad microwave curing method. Fabrics were padded, using two dip and two nip process that is commonly used in textile industry for absorption of desired components in desired quantity, first with an aqueous solution containing crosslinking agent(s), acid catalyst, a catalyst activator and then with neem extract in combination with coreactant. The cross-linking agents used are Dimethlylol dihydroxy ethyleneurea (DMDHEU), glyoxal and polycarboxlic acids such as citric acid (CA) and BTCA. The concentration of cross-linking agent ranges from 2 to 15 % by wt. and the curing is carried out at a temperature between 115 to 200°C depending on the type of crosslinking agent. The major problem associated with DMDHEU treated fabric is that the free formaldehyde is librated during processing and the storage of the fabric, which is carcinogenic and not suitable for health and hygiene point of view. The major problem associated with polycarboxalic acids (BTCA/CA) is that the presence of sodium hypophosphite produces shade change in certain dyed fabric. BTCA/CA are also not cost effective. Glyoxal, non-formaldehyde, is the best alternative as crosslinking agent for cellulosic fabric as it has low cost and easily available. The acid acid catalysts employed may be such as magnesium chloride, aluminum sulphate, sodium bisulphate and zirconium sulphate. It has been found that aluminum sulphate is most effective catalyst for crosslinking of cotton. The limitation with this catalyst is that it tends to cause fabric yellowing and very high strength loss. However, adding one mole of ethylene glycol per mole of glyoxal can reduce the yellowing. The glycol having chain length of 2-8 carbon atoms exclusive of terminal hydroxyl groups, is added as a co-reactant of glyoxal and the addition of an equimolar quantities, greatly increase the crease recovery angle of the treated cotton. The addition of a hydroxyl acid such as tartaric acid, glycolic acid, lactic acid, succinic acid as an catalyst activator prove to reduce the temperature of curing. It is found that tartaric acid is most effective catalyst activator for aluminum sulphate and reduces the curing temperature up to 115°C.The wet expression given to the samples were 100-110%. Higher wet expression is needed for smooth functioning of drying and curing, particularly when microwave is used for this purpose, as water is acting as a major heat transfer material. Subsequently fabrics were dried and cured simultaneously at various wave frequencies in the range of 1 GHz to 40 GHz preferably in a microwave oven at different powers ranging from 200w to 2000w for different time from about less than 1 min. Microwave provides sufficient energy for cross-linking as well as retains the activity of neem ingredients. Cross-linking of compound using microwave energy may be attributed to rearrangement of H- bond. Another advantage of microwave curing is that it provides uniform heating to the sample so that ingredients have not migrated on to the surface and retained the strength losses after cross-linking. The amounts of strength retention of the samples were in the range of 80%-90%. Cured fabrics were subjected to hot wash and then cold wash. The fabrics were dried at room temperature. The final weight add on percent of the samples were in the range of 1-10%. After drying, antibacterial properties of the finished samples were evaluated by using AATCC 147-1975 test method using Staphylococcus aureus and Bacillus subtilis as bacterial species. It was found that neem extracts concentration ranging from 0.1% to 5% were sufficient to inhibit the growth of test bacterium. The invention is further illustrated and substantiated by the following experimental procedures. However, this should not limit the scope of the invention. GENERAL A desized, scoured and bleached plain weave (104 ends X 86 picks) cotton fabric weighing 112gm/m was used. Neem seed extract and bark extract were procured from EID parry (I) Ltd. Glyoxal (C2H2O2, Thomas Baker, 40%aqueous solution) was used as crosslinking agent. Aluminum sulfate (Al2 (SO4) 3.18 H2O, Merck) was used as catalyst. Tartaric acid (C4H6O6, Merck) was used as catalyst activator and ethylene glycol (C2H6O2, Merck) was used as coreactant additive. All the chemicals used were reagent grade. CHARACTERIZATION OF NEEM EXTRACT Neem extract have been characterized by using high performance liquid chromatography (HPLC). An Agilent make HPLC system equipped with UV/VIS detector, reverse phased C-18 Column (25 cm x 4 mm, 5 u particle size) was used for analytical work. The peak was detected at 214 nm for all the limonoids used. Analysis of azadirachtin was carried out using isocratic mobile phase of acetonitrile: water :: 35:65. Analysis of nimbin and Salannin were carried out using isocratic mobile phase of acetonitrile : water:: 50:50. Table 1 shows the percent concentration by mass of each limonoid in seed and bark extract. Table 1: (Table Removed) EXAMPLE 1 The fabric samples were padded, using two dip and two nip process, in a solution containing crosslinking agent glyoxal (11.6% w/v), catalyst aluminum sulphate (4% by wt of crosslinking agent) and catalyst activator tartaric acid (4% by wt of crosslinking agent), then padded in a 60% solution of methanol containing neem seed/bark extract and coreactant ethylene glycol (12.4%). The wet expression given to the samples were 100-110%. Immediate after padding, the fabric samples were dried and cured simultaneously in the microwave chamber (MICROWAVE LABSTATION, MILESTONE, MLS 1200, MEGA) at 200W power for 1 min. EXAMPLE 2 The fabric samples were padded, using two dip and two nip process, in a solution containing crosslinking agent glyoxal (11.6% w/v), catalyst aluminum sulphate (4% owr) and catalyst activator tartaric acid (4% owr), then padded in a 60% solution of methanol containing neem seed/bark extract and coreactant ethylene glycol (12.4%). The wet expression given to the samples were 100-110%. Immediate after padding fabric samples were dried at 85°C for 5min and cured at 120°C for 2 min. The finished fabrics were washed in Launder-o-meter according to AATCC test method 124-1975, under the test no. II A. The finished fabrics were tested using washed and unwashed samples for antimirobial and anticrease property using conventional standard procedures as described below. Antibacterial activity of the samples was evaluated qualitatively by using parallel streak method (AATCC 147-1975 ) using Staphylococcus aureus and Bacillus subtilis as test bacterium. For quantitative test, rectangular (2"X1") sample swatches were exposed to 20ul of bacterial inoculum containing 1.0x108 cm/ml using agar plate method. After 24 hours incubation, swatches were placed in sterilized flask containing 10 ml sterilized distilled water. Flask was shaken for 1 hr at 150 rpm on laboratory shaker, to release the bacteria from the fabric. Serial dilutions of the liquid were made in sterilized water. Dilution of 10-3, 10-4 and 10-5 were used for colony counting. 20 µl were spread on to the agar plate and plates were incubated at 30°C for 24 hrs. After incubation bacterial colonies were counted. The antibacterial activity was calculated by using following equation. (Equation Removed) Where, A = No. of colonies in control sample B = No. of colonies in treated sample The antibacterial activity of seed extract treated unwashed samples against Staphylococcus aureus and Bacillus subtilis using parallel Streak method is shown in Figure 1 accompanying this specification. It is observed that the conventionally cured samples show the maximum zone of inhibition of 4.56 cm for Staphylococcus aureus created by 10% seed extracts treated fabric and 2.5 cm for Bacillus subtilis created by 5% seed extract treated samples. While in case of microwave cured samples the maximum zone of inhibition (3.67cm for Staphylococcus aureus and 2.16 cm for Bacillus subtilis) created by 5% seed extract treated samples. The antibacterial activity of seed extract treated fabric after 1st wash is given in Table 2. TABLE 2 (Table Removed) Note: W = washed; Con = Control; CC = Conventional curing MW = Microwavw curing SE = Seed extract It may be noted that the antibacterial activity of seed extract treated fabric is higher for Staphylococcus aureus as compared to Bacillus subtilis. However, there is no significant difference between microwave cured and conventional cured samples. It was further observed that the antibacterial property is retained at least up to five washes as shown in figures 2 and 3 accompanying this specification. The bark extract treated samples appear to have higher antibacterial property against Staphylococcus aureus. EVALUATION OF FABRIC PROPERTIES Standard methods were used to measure wrinkle recovery angles (AATCC-66-1975), Elmendorf tearing strength (ASTM-1424-2000) and strip breaking strength (ASTM-D5035-90). Test measurements were made in the warp direction for tearing and breaking strength. The tensile strength of seed and bark extract treated sample cured by both conventional and microwave curing method is shown in Figure 4. Microwave cured samples (97%) showed higher retention tensile strength as compared to conventional cured samples (84%). There is no significant change in tensile strength of neem seed and bark extract treated samples as compared to control sample. The control sample is a sample treated with all components except neem extract. TEARING STRENGTH The tearing strength of neem seed and bark extract treated samples cured by both conventional and microwave method is shown in Figure 5. Microwave cured (95%) samples showed higher retention in tearing strength as compared to the conventional cured sample (81%). The retention in tearing strength of conventional cured sample improved as compared to the control sample. CREASE RECOVERY The crease recovery angle of seed and bark extract treated sample is shown in Figure 6. The crease recovery angle as can be seen from the figure is higher for conventional cured sample as compare to microwave cured samples. There is drop in crease recovery angle of seed extract treated fabric as compared to control sample. There is no significant change in crease recovery angle of bark extract treated sample as compared to control sample. ADVANTAGES: 1. The process is user friendly as it employes safe natural antimicrobial agent derived from neem 2. This is a simple and ecofriendly process. 3. Cost effective method in comparison to the existing methods. 4. Lesser application time for finishing process. 5. Lower power consumption. 6. Fabric produced : a. Has anti-microbial properties b. Has non allergic and skin friendly properties c. Has crease resistant properties d. Has a potential use as dressing material or dermal patch for curing infection. We Claim: 1. A process for inducting anti-microbial and anti crease property in textile material comprising (i) exposing the textile material intended to get inducted with the antimicrobial and anticrease property by two dip and two nip process to a composition comprising crosslinking agent, acid catalyst, and a hydroxyl acid as a catalyst activator then exposing by padding to the solution of limonoids extracted from neem containing coreactant to crosslinking agent so as to get 100 to 110 % wet expression on the material or 1.3 to 8.099% of neem extract or 0.1 to 1.15% of limonoid get inducted in the material, (ii) drying and curing the material at 1 GHz to 40 GHz employing microwave for not exceeding 1 minute or at a temperature ranging from 115°C to 125°C preferably at 120°C for up to 2 minutes in an oven to get anti-microbial and anti crease property inducted textile material. 2. A process as claimed in claim 1 wherein the textile material used is exemplified by cotton, cotton polyester blend fabric or yarn preferably fabric. 3. A process as claimed in claim 1 wherein the two dip and two nip process is effected by dipping the material in the said composition and removing excess composition twice to facilitate the composition to get absorbed in the material. 4. A process as claimed in claim 1 wherein the crosslinking agent used is selected from Dimethlylol dihydroxy ethyleneurea (DMDHEU), glyoxal, polycarboxlic acids such as citric acid (CA) and BTCA preferably glyoxal and is employed in the range of 2 to 15 % by wt. Preferably 5% by wt. of total composition. 5. A process as claimed in claim 1 wherein the acid catalyst used is magnesium chloride, aluminum sulphate, sodium bisulphate or zirconium sulphate preferably aluminum sulphate when fabric to be treated is cotton, and added in the range of 0.1 to 8 % by wt. Preferably 4 % by wt. of crosslinking agent. 6. A process as claimed in claim 1 wherein the a hydroxyl acid is tararic acid, glycolic acid, lactic acid, succinic acid preferably tartaric acid when catalyst is aluminum sulphate and is employed in the range of 2 to 6% preferably 4% by wt. of crosslinking agent. 7. A process as claimed in claim 1 wherein the limonoids are extracted from seed or bark of neem. 8. A process as claimed in claim 1 wherein the co-reactant to crosslinking agent used is glycol having chain length of 2-8 carbon atoms exclusive of terminal hydroxyl groups, preferably ethylene glycol and is added in equimolar quantities o crosslinking agent exemplified by glyoxal. 9. A process for inducting anti-microbial and anti crease property in textile material substantially as herein described with reference to examples and drawings accompanying this specification.

Documents:

1679-DEL-2004-Abstract-(15-06-2012).pdf

1679-del-2004-abstract.pdf

1679-DEL-2004-Claims-(15-06-2012).pdf

1679-del-2004-claims.pdf

1679-DEL-2004-Correspondence Others-(15-06-2012).pdf

1679-del-2004-correspondence-others.pdf

1679-DEL-2004-Description (Complete)-(15-06-2012).pdf

1679-del-2004-description (complete).pdf

1679-del-2004-description (provisional.pdf

1679-del-2004-drawings.pdf

1679-del-2004-form-1.pdf

1679-del-2004-form-18.pdf

1679-DEL-2004-Form-2-(15-06-2012).pdf

1679-del-2004-form-2.pdf

1679-del-2004-form-3.pdf

1679-del-2004-form-5.pdf

1679-del-2004-gpa.pdf