Description:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
As amended by the Patents (Amendment) Act, 2005
&
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2006
COMPLETE SPECIFICATION
(See section 10 and rule 13)

TITLE OF THE INVENTION
A MULTI-FUNCTIONAL TEXTILE PRODUCT WITH FAR INFRARED REFELECTIVE PROPERTY

APPLICANT
Aditya Birla Science and Technology Company Pvt Ltd. an Indian company having its address at Aditya Birla Centre, 2nd Floor, ‘C’wing, S. K. Ahire Marg, Worli, Mumbai 400030, Maharashtra, India; and
Birla Century (A Division of Century Textiles & Industries Ltd), having its address at 826, GIDC Industrial Estate, Jhagadia, Bharuch-393110, Gujarat, India

PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed:

FIELD OF THE INVENTION
[001] The present invention relates to a far infrared reflective (FIR) additive, a multi-functional composition comprising the same, and a method of applying the multi-functional composition to a fabric.
BACKGROUND OF THE INVENTION
[002] Far infrared radiation (3-100 µm) is a subdivision of the electromagnetic spectrum and transfers energy purely in the form of heat. Human bodies produce electromagnetic radiation in the form of, for example, heat or infrared radiation. The human body loses most of its heat through FIR radiation (60%). Humans at normal body temperature radiate most strongly in the infrared at a wavelength of about 10 µm. Various approaches have been reported for preparation of far Infrared reflective (FIR) fabric.
[003] As reported in various literatures, FIR fabrics can promote blood circulation and increase oxygen levels in the blood. The additional energy generated can have many positive effects on the body, such as performance enhancement and prevention of premature fatigue, as well as improved tissue and muscle regeneration.
[004] Apart from FIR properties, human comfort as well as hygiene are also other important attributes to be considered. Various methods of making multifunctional fabric including FIR properties along with other functional attributes have been reported.
[005] CN110791828 discloses the making of multifunctional regenerated cellulose fiber using lavender essentials oil & nanographene. Fabric made from this regenerated cellulosic fiber shows antibacterial, antistatic properties along with IR emissivity> 88 and is useful in the fields of bedding, clothing, and medical supplies.
[006] EP3192902B1 relates to a viscose fiber made by adding graphene in viscose dope. Improvement in the far-infrared functions as well as antibacterial properties have been reported.
[007] CN108691199A relates to a kind of antibacterial far infrared health care cellulose fiber and its preparation method and application.
[008] Achieving multifunctional attributes in fabric along with comfort and durability remains a key challenge. Therefore, there exists a need for a novel formulation having FIR reflective property and for products comprising this attribute along with other attributes such as wrinkle free, moisture management along with comfort.
SUMMARY OF THE INVENTION
[009] In one aspect, the present invention is directed to a far infrared reflective (FIR) additive comprising a mixture of a metal oxide with silicate and/or talc.
[010] In an embodiment, the FIR additive is an aqueous suspension comprising the mixture in a non-ionic surfactant.
[011] In another embodiment, the metal oxide is selected from Cerium oxide (CeO2), Titanium oxide (TiO2), Zirconium oxide (ZrO2), and Aluminium oxide (Al2O3). Preferably, the metal oxide is Cerium oxide (CeO2).
[012] In a further embodiment, the silicate is selected from silicates of Cerium, Titanium, Zirconium, and Aluminium. Preferably, the silicate is calcium aluminosilicate.
[013] In still another embodiment, the mixture contains 10 wt.% to 30 wt.% of the metal oxide, and 70 wt.% to 90 wt.% of the silicate and/or talc. The wt.% is based on the total weight of the additive.
[014] In another aspect, the present invention is directed to a multi-functional composition. The composition comprises: 5.0 wt.% to 10.0 wt.% of at least one cross-linking agent, 0.5 wt.% to 2.0 wt.% of at least one catalyst and/or activator, 2.0 wt.% to 5.0 wt.% of at least one binder, 4.0 wt.% to 12.0 wt.% of at least one fabric softener, 0.5 wt.% to 2.0 wt.% of at least one dispersing agent, and 2.0 wt.% to 8.0 wt.% of at least one far infrared reflective (FIR) additive comprising a mixture of a metal oxide with a silicate and/or talc. The wt.% is based on the total weight of the composition.
[015] In an embodiment, the cross-linking agent is a Methylol dihydroxyethylene urea-based resin.
[016] In another embodiment, the catalyst and/or activator is selected from magnesium chloride, magnesium fluoride, magnesium nitrate, sodium acetate, ammonium chloride, zinc nitrate, zinc chloride, and zinc fluoroborate.
[017] In still another embodiment, the binder is an acrylic binder selected from ethyl acrylate, butyl acrylate, and styrene acrylate.
[018] In yet another embodiment, the fabric softener is a silicone softener and/or a polyethylene softener. Preferably, the silicone softener is selected from ternary blocked hydrophilic silicone emulsions, amino silicones, and quat silicones.
[019] In a still further embodiment, the dispersing agent is selected from acrylic based dispersing agents, naphthalene based dispersing agents, and lignin sulphonate based dispersing agents.
[020] In a further aspect, the present invention is directed to a method for preparing a multi-functional composition. The method comprises blending a mixture of a metal oxide with a silicate and/or talc in the presence of a non-ionic surfactant and water to obtain an aqueous suspension of far infrared reflective (FIR) additive. Subsequently, mixing 2.0 wt.% to 8.0 wt.% of the far infrared reflective (FIR) additive aqueous suspension with the following: 5.0 wt.% to 10.0 wt.% of at least one cross-linking agent, 0.5 wt.% to 2.0 wt.% of at least one catalyst and/or activator, 2.0 wt.% to 5.0 wt.% of at least one binder, 4.0 wt.% to 12.0 wt.% of at least one fabric softener, and 0.5 wt.% to 2.0 wt.% of at least one dispersing agent to obtain the multi-functional composition. The wt.% is based on the total weight of the composition. Further, the at least one far infrared reflective (FIR) additive comprises a mixture of a metal oxide with a silicate and/or talc.
[021] In an embodiment, the suspension has a Dv90 particle size of less than 5microns.
[022] In another embodiment, mixing is carried out at a speed ranging between 1500 rpm to 2500 rpm.
[023] In yet another embodiment, a pH adjusting agent is added to maintain the pH of the multi-functional composition between 4.0 to 6.5.
[024] In still another aspect, the present invention is directed to a method of applying a multi-functional composition to a fabric. The method comprises coating the fabric with the multi-functional composition comprising: 5.0 wt.% to 15.0 wt.% of at least one cross-linking agent, 0.5 wt.% to 2.0 wt.% of at least one catalyst and/or activator, 1.0 wt.% to 5.0 wt.% of at least one binder, 4.0 wt.% to 12.0 wt.% of at least one fabric softener, 0.5 wt.% to 2.0 wt.% of at least one dispersing agent, and 2.0 wt.% to 10.0 wt.% of at least one far infrared reflective (FIR) additive comprising a mixture of a metal oxide with a silicate and/or talc, to obtain the coated fabric. The wt.% is based on the total weight of the composition. Thereafter, drying and curing the coated fabric at a temperature ranging between 120°C-190°C to obtain a finished FIR fabric having a retention of at least 50% with respect to the infrared reflective (FIR) additive.
[025] In an embodiment, the fabric has multi-functional properties of one or more thermal insulation, far infrared reflective, wrinkle free, and moisture management.
[026] In another embodiment, the fabric meets the requirements of far infrared radiation in accordance with GB/T 30127-2013, wrinkle free (durable press) in accordance with AATCC 124-2014, moisture management (wicking height) in accordance with AATCC 197-2013.
DETAILED DESCRIPTION OF THE INVENTION
[027] Before the compositions and formulations of the present invention are described, it is to be understood that this invention is not limited to particular compositions and formulations described, since such compositions and formulation may, of course, vary. It is also to be understood that the terminology used herein is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.
[028] The terms “comprising”, “comprises” and “comprised of” as used herein are synonymous with “including”, “includes” or “containing”, “contains”, and are inclusive or open-ended and do not exclude additional, non-recited members, elements or method steps. It will be appreciated that the terms “comprising”, “comprises” and “comprised of” as used herein comprise the terms “consisting of”, “consists” and “consists of”.
[029] Furthermore, the terms “first”, “second”, “third” or “(a)”, “(b)”, “(c)”, “(d)” etc. and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein. In case the terms “first”, “second”, “third” or “(A)”, “(B)” and “(C)” or “(a)”, “(b)”, “(c)”, “(d)”, “i”, “ii” etc. relate to steps of a method or use or assay there is no time or time interval coherence between the steps, that is, the steps may be carried out simultaneously or there may be time intervals of seconds, minutes, hours, days, weeks, months or even years between such steps, unless otherwise indicated in the application as set forth herein above or below.
[030] In the following passages, different aspects of the present invention are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.
[031] Reference throughout this specification to “one embodiment” or “an embodiment” 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 one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to a person skilled in the art from this disclosure, in one or more embodiments. Furthermore, while some embodiments described herein include some, but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the appended claims, any of the claimed embodiments can be used in any combination.
[032] Furthermore, the ranges defined throughout the specification include the end values as well, i.e., a range of 1 to 10 implies that both 1 and 10 are included in the range. For the avoidance of doubt, the applicant(s) shall be entitled to any equivalents according to applicable law.
[033] In the present context, “far infrared” or “far infrared spectrum” refers to wavelengths ranging between 3 µm to 100 µm. Accordingly, the phrase “far infrared reflective (FIR) additive” refers to an additive or a composition specifically designed to enhance the reflective properties of surfaces within the far infrared spectrum.
[034] Further, the term "alkyl" refers to a saturated hydrocarbon moiety derived from alkanes by the removal of one hydrogen atom. The alkyl group may be linear or branched and typically consists of carbon and hydrogen atoms. Examples of alkyl groups include, but are not limited to, methyl (CH3), ethyl (C2H5), propyl (C3H7), nonyl (C9H19), and the like.
[035] “Aryl” refers to an aromatic hydrocarbon moiety derived from benzene or a similar aromatic ring by the removal of one hydrogen atom. The aryl group may be a single aromatic ring or a fused ring system and typically consists of carbon and hydrogen atoms. Examples of aryl groups include, but are not limited to, phenyl (C6H5), naphthyl (C10H7), and the like.
[036] Herein, “fabric” encompasses a textile structure or material comprising interwoven or interconnected fibers, filaments, or threads. The fabric may be composed of natural or synthetic materials and can exhibit a variety of physical characteristics, including but not limited to flexibility, durability, and texture. In the context of this invention, the term encompasses woven, knitted, non-woven, or other textile configurations.
[037] In the present context, “finished FIR fabric” refers to a textile structure or material that has undergone a series of processing steps and treatments to achieve specific characteristics, properties, or functionalities. These processing steps may include, but are not limited to, weaving, knitting, dyeing, printing, coating, laminating, finishing, drying, curing, and any other treatment contributing to the final form of the fabric. As described herein, the finished fabric is obtained after coating with the FIR additive, optionally in the presence of other additives and/or auxiliaries, referred to as a multifunctional composition. The finished fabric may exhibit desired attributes such as FIR reflective, wrinkle free, moisture management along with comfort, colorfastness, texture, durability, resistance to environmental factors, and any other features resulting from the applied treatments. The term encompasses fabrics intended for use in various applications, including but not limited to apparel, upholstery, industrial applications, and technical textiles.
[038] Herein, “retention” in the context of finished FIR fabric implies the capability of the fabric to hold the FIR additive onto its surface. The retention may be determined as a percentage ratio of the amount of the FIR additive remaining on the surface of the finished FIR fabric to the amount of FIR additive originally used on the fabric during coating. Retention on the FIR fabric can also be directly correlated with ash% in the finished FIR fabric, whereby the amount of metal oxide and silicate (both in talc as well as otherwise) is determined. The ash% in the fabric therefore directly provides an indication that the fabric contains the FIR additive of the present invention.
[039] An aspect of the present invention relates to a far infrared reflective (FIR) additive.
[040] In an embodiment, the FIR additive comprises a mixture of a metal oxide with a silicate and/or talc.
[041] Accordingly, in a preferred embodiment the FIR additive includes the mixture of metal oxide with silicate.
[042] In another preferred embodiment, the FIR additive includes the mixture of metal oxide with talc.
[043] In yet another preferred embodiment, the FIR additive includes the mixture of metal oxide, silicate, and talc.
[044] Silicates in the present invention absorb infrared radiation and radiate it back to the body in the far infrared region, whereas the metal oxides are capable of reflecting the infrared radiation.
[045] Suitable metal oxide can be selected from Cerium oxide (CeO2), Titanium oxide (TiO2), Zirconium oxide (ZrO2), and Aluminium oxide (Al2O3). Preferably, the metal oxide is Cerium oxide (CeO2).
[046] Suitable silicates can be selected from silicates of Cerium, Titanium, Zirconium, and Aluminium. Further, silicates in the present context also include mixed silicates having one or more of Cerium, Titanium, Zirconium, and Aluminium, optionally with one or more of Magnesium, Calcium, and Zinc. For instance, silicates of cerium include cerium(III) metalsilicate (Ce2SiO5), cerium(II) orthosilicate (Ce2(SiO4)3), and cerium(IV) silicate (CeSiO4). Silicates of titanium include titanium silicate, Titanium Aluminosilicate, and Magnesium Titanosilicate (MgTiSiO5). Silicates of zirconium include zirconium silicate (ZrSiO4), Zirconium Orthosilicate (ZrSiO4), and Zirconium Disilicate (ZrSi2O7). Silicates of aluminum include Aluminosilicate, Calcium aluminosilicate, Andalusite (Al2SiO5), Muscovite Mica (KAl2(AlSi3O10)(OH)2), Feldspar Group (e.g., Orthoclase, KAlSi3O8), and Kaolinite (Al2Si2O5(OH)4).
[047] In a preferred embodiment, the silicate is calcium aluminosilicate.
[048] Herein, “talc” refers to a hydrous magnesium silicate mineral characterized by its lamellar structure and chemical composition predominantly consisting of magnesium, silicon, and oxygen. Talc is represented by the chemical formula Mg3Si4O10(OH)2 and is commonly found in nature as a metamorphic mineral. Further, talc encompasses both natural occurrences and synthetically produced talc materials. The term is understood to cover talc in its various forms, including finely ground powders. In an embodiment, the particle size Dv90 of the powder is less than 5 microns, preferably ranging between 1 micron to 5 micron determined in a particle size analyzer such as Mastersizer 2000 by Malvern Instruments Ltd.
[049] In yet another embodiment, the mixture contains 10 wt.% to 30 wt.% of the metal oxide, and 70 wt.% to 90 wt.% of the silicate and/or talc. Herein, wt.% is based on the total weight of the additive.
[050] Accordingly, in a preferred embodiment the FIR additive includes the mixture containing 10 wt.% to 30 wt.% of the metal oxide, and 70 wt.% to 90 wt.% of the silicate.
[051] In another preferred embodiment, the FIR additive includes the mixture containing 10 wt.% to 30 wt.% of the metal oxide, and 70 wt.% to 90 wt.% of the talc.
[052] In yet another preferred embodiment, the FIR additive includes the mixture containing 10 wt.% to 30 wt.% of the metal oxide, and 70 wt.% to 90 wt.% of silicate and talc.
[053] In another embodiment, the FIR additive is an aqueous suspension comprising the above mixture in a non-ionic surfactant. Suitable non-ionic surfactants include C5-C50 carbon alcohol ethoxylates and/or mixtures thereof.
[054] In a preferred embodiment, the non-ionic surfactant is an alkyl aryl ether phosphate such as nonyl phenol ethoxylate phosphate ester and polyoxyethylene alkylphenol ether phosphate.
[055] Alkyl aryl ether phosphate is derived from the reaction of an alkyl aryl ether with phosphoric acid, resulting in the formation of a phosphate ester. The alkyl aryl ether component encompasses an alkyl group and an aryl group linked by an ether linkage, with the aryl group further including at least one aromatic ring. Alkyl aryl ether phosphate may be represented by the following general formula:
R-O(Ar)-OP(O)(OH)2
wherein,
R represents an alkyl group,
Ar represents an aryl group comprising at least one aromatic ring,
-O represents the ether linkage, and
-OP(O)(OH)2-OP(O)(OH)2 represents the phosphate ester group resulting from the reaction with phosphoric acid.
[056] Nonyl phenol ethoxylate phosphate ester is derived from the ethoxylation of nonyl phenol, involving the addition of ethylene oxide units to the nonyl phenol hydrophobic moiety, followed by esterification with phosphoric acid. The resulting ester exhibits a unique combination of hydrophobic and hydrophilic elements, rendering it suitable for application in the present invention. Nonyl phenol ethoxylate phosphate ester may be represented by the following general formula:
R-C6H4-O(CH2CH2O)n-OP(O)(OH)2
wherein,
R represents a nonyl group (C9H19),
C6H4 represents a phenolic ring,
-O(CH2CH2O)n represents the ethoxylate chain resulting from the ethoxylation of the phenolic hydroxyl group with ‘n’ indicating the number of ethylene oxide units and ranging between 1 to 30,
-OP(O)(OH)2 represents the phosphate ester group resulting from the esterification of the ethoxylated nonyl phenol with phosphoric acid.
[057] The polyoxyethylene alkylphenol ether phosphate may be similarly represented as Nonyl phenol ethoxylate phosphate ester, by the following general formula:
RO-C6H4-(CH2CH2O)n-OP(O)(OH)2
wherein,
R represents an alkyl group,
C6H4 represents a phenolic ring,
-O(CH2CH2O)n represents the ethoxylate chain resulting from the ethoxylation of the phenolic hydroxyl group with ‘n’ indicating the number of ethylene oxide units and ranging between 1 to 30,
-OP(O)(OH)2 represents the phosphate ester group resulting from the esterification of the ethoxylated nonyl phenol with phosphoric acid.
[058] Suitable non-ionic surfactant in the present invention may also be characterized in terms of their properties, such as HLB value, and surface tension. For instance, the HLB value of the non-ionic surfactant ranges between 10 to 15, whereas surface tension ranges between 20 mN/m to 60 mN/m.
[059] The FIR additive, as described herein, may be used directly or in combination with a finishing formulation on a fabric which provides further attributes. When the FIR additive is combined with the finishing formulation, a multifunctional composition is obtained. The multifunctional composition provides for various attributes in a finished FIR fabric such as FIR reflective, wrinkle free, moisture management along with comfort, colorfastness, texture, durability, and resistance to environmental factors.
[060] Another aspect of the present invention relates to a process for preparation of the FIR additive, as described hereinabove. Accordingly, the embodiments pertaining to the FIR additive are applicable here as well.
[061] In an embodiment, the process comprises mixing/blending the mixture and non-ionic surfactant with water.
[062] Yet another aspect of the present invention relates to a multi-functional composition. The multifunctional composition comprises the FIR additive, as described hereinabove. Accordingly, the embodiments pertaining to the FIR additive are applicable here as well.
[063] In an embodiment, the multifunctional composition comprises: 5.0 wt.% to 15.0 wt.% of at least one cross-linking agent, 0.5 wt.% to 2.0 wt.% of at least one catalyst and/or activator, 1.0 wt.% to 5.0 wt.% of at least one binder, 4.0 wt.% to 12.0 wt.% of at least one fabric softener, 0.5 wt.% to 2.0 wt.% of at least one dispersing agent, and 2.0 wt.% to 10.0 wt.% of at least one of the FIR additive, as described above. Remaining being water. The wt.% is based on the total weight of the multifunctional composition.
[064] Suitable crosslinking agent includes N-Methylol dihydroxyethylene urea-based resins. In an embodiment, the amount of crosslinking agent in the multifunctional composition ranges between 5.0 wt.% to 12.0 wt.%, or 5.0 wt.% to 10.0 wt.%, or 5.0 wt.% to 8.0 wt.%.
[065] Suitable catalyst and/or activator can be selected from magnesium chloride, magnesium fluoride, magnesium nitrate, sodium acetate, ammonium chloride, zinc nitrate, zinc chloride, and zinc fluoroborate. In a preferred embodiment, the catalyst and/or activator is selected from magnesium chloride, magnesium fluoride, magnesium nitrate, sodium acetate, and ammonium chloride. In another preferred embodiment, the catalyst and/or activator is magnesium chloride.
[066] In an embodiment, the catalyst and/or activator is present in an amount ranging between 0.5 wt.% to 2.0 wt.%, or 0.5 wt.% to 1.5 wt.%, or 0.75 wt.% to 1.5 wt.%.
[067] Suitable binder is an acrylic binder selected from ethyl acrylate, butyl acrylate, and styrene acrylate. Acrylic copolymer binders may also be used in the present invention.
[068] In an embodiment, the binder is present in an amount ranging between 1.0 wt.% to 4.0 wt.%, or 1.0 wt.% to 3.0 wt.%, or 1.0 wt.% to 2.0 wt.%.
[069] Suitable fabric softener includes a silicone softener and/or a polyethylene softener.
[070] In an embodiment, softeners include a macro silicone softener and/or a micro silicone softener. Macro silicone softener is a macro emulsion and provides for durable, hydrophilic silicone softening and smoothing of textile products of all fiber types and confer voluminous handle effects. Micro silicone softeners include silicone quaternary polymer microemulsions and provide for hydrophilic silicone softening and smoothing of textile products of all fiber type, as well as stability over wide pH range. Preferably, the macro softener has a density ranging between 0.98 g/cc to 1.20 g/cc at 20?C, whereas the micro softener has a density ranging between 0.96 g/cc to 0.98 g/cc at 20?C.
[071] In another embodiment, the silicone softener is selected from ternary blocked hydrophilic silicone emulsions, amino silicones, and quat silicones. Suitable polyethylene softener includes low, medium, and high-density oxidized polyethylene emulsions. Preferably, the polyethylene softener has a molecular weight (Mw) of 1000 g/mol to 3000 g/mol.
[072] Suitable dispersing agents can be selected from acrylic based dispersing agents, naphthalene based dispersing agents, and lignin sulphonate based dispersing agents.
[073] In an embodiment, the dispersing agent is naphthalene based dispersing agent. Suitable naphthalene based dispersing agent includes condensation product of sulfonated naphthalene with formaldehyde and/or urea.
[074] In an embodiment, the dispersing agent is present in an amount ranging between 0.5 wt.% to 2.0 wt.%, or 0.5 wt.% to 1.5 wt.%, or 0.75 wt.% to 1.5 wt.%.
[075] The multifunctional composition optionally includes further ingredients and/or auxiliaries which may provide additional attributes to the finished fabric and/or aid during processing of the fabric. Such further ingredients and/or auxiliaries include pH adjusting agent, flame retardants, UV absorbers, antimicrobial agents, anti-corrosion agents, plasticizers, rheology modifiers, and the likes. Suitable amounts of these further ingredients and/or auxiliaries are known to the person skilled in the art.
[076] The multifunctional composition is typically applied on a fabric to obtain a finished product. Suitable fabrics for this purpose can be selected from Sheeting, Yarn Dyed, Solid Dyed, and other conventional fabrics. Typically, cellulosic fabric including 100% cotton and its blend with other commercially available cellulosic fiber are used for making the finished product, i.e., finished FIR fabric. Other fabrics include natural cellulosic fibers, man-made cellulosic fibers, blends of natural and man-made cellulosic fibers (for e.g., nylon) based fabric.
[077] Yet another aspect of the present invention relates to a method for preparing the multifunctional composition, as described above. Accordingly, the embodiments pertaining to the multifunctional composition and the FIR additive are applicable here as well.
[078] The method comprises obtaining the FIR additive. For this, the mixture of the metal oxide with the silicate and/or talc is blended in the presence of the non-ionic surfactant and water to obtain the aqueous suspension of the FIR additive. The suspension has a solid content ranging between 20-60 wt.%. In an embodiment, the suspension has a Dv90 particle size of less than 5microns. The particle size distribution is determined in a particle size analyzer such as Mastersizer 2000 by Malvern Instruments Ltd.
[079] Subsequently, the finishing formulation is mixed with the FIR additive suspension, with various ingredients described above in suitable amounts. Herein, mixing is carried out using suitable mixing means such as a mixer or stirrer. The mixing is carried out at a speed ranging between 1500 rpm to 2500 rpm. During the mixing step, further ingredients and/or auxiliaries may be added in suitable amounts.
[080] The multifunctional composition as obtained above is applied on suitable fabric or textile product.
[081] Still another aspect of the present invention relates to a method of applying the multifunctional composition to the fabric, as described hereinabove. Accordingly, the embodiments pertaining to the multifunctional composition and the FIR additive are applicable here as well.
[082] Suitable fabric is coated with the multifunctional composition to obtain a coated fabric. For this, the fabric may be subjected to padding. Herein, padding refers to applying the multifunctional composition coating by passing the fabric through a bath and subsequently through squeeze rollers. The person skilled in the art is aware of the padding technique and means therefor.
[083] In an embodiment, the method steps include padding, squeezing, and drying, which may be performed in a machine called “Stenter”. The ingredients of the multifunctional composition, as described herein, may be applied through a trough attached to a continuous replenishment mechanism. The ingredients are evenly distributed on the fabric through a set of pneumatically operated padding mangle. The padding mangle helps in even distribution of the ingredients on the fabric, maintaining proper add on percentage of the ingredients and moisture through pick up. In an embodiment, the add on percentage is maintained in the range of 0.1% to 10 % and the pick-up percentage is in the range of 30% to 75%. In the final section of the Stenter, the fabric is dried evenly with a moisture regain of 0.5 % to 10 %.
[084] In another embodiment, the Stenter contains several drying chambers, for example up to 12. Depending on the moisture regain on the fabric, which may vary from 0.5% to 10%, and speed of production, the number of drying chambers used in the Stenter will be decided, with a temperature of about 150°C to 180°C being maintained in each of the chambers.
[085] In another embodiment, the coated fabric is dried and cured at a temperature ranging between 120°C-190°C to obtain the finished FIR fabric. In an embodiment, the coated fabric may be subjected to drying at a temperature ranging between 120°C-170°C, followed by curing at a temperature ranging between 150°C-190°C.
[086] The finished FIR fabric has a retention of at least 50% with respect to the FIR additive.
[087] The finished FIR fabric has multifunctional properties and/or attributes of at least thermal insulation, FIR reflective, wrinkle free, and moisture management. Furthermore, the finished FIR fabric of the present invention is sustainable, ZDHC certified. and is durable up to 75 washes.
[088] In fact, the finished FIR fabric meets the requirements of far infrared radiation in accordance with GB/T 30127-2013, wrinkle free (durable press) in accordance with AATCC 124-2014, moisture management (wicking height) in accordance with AATCC 197-2013.
[089] Still further aspect of the present invention relates to the finished FIR fabric, as described above. Accordingly, the embodiments pertaining to the method of applying the multifunctional composition to the fabric are applicable here as well.
[090] In an embodiment, the finished FIR fabric includes bed linens, home furnishing and upholstery items, bottom weights, shirting, formal, casual and the likes, having attributes such as FIR reflective, wrinkle free, moisture management along with comfort, colorfastness, texture, durability, and resistance to environmental factors.
EXAMPLES
[091] The following examples are illustrative of the present invention but not limitative of the scope thereof:
[092] Ingredients
Crosslinking agent N-Methylol dihydroxyethylene urea
Catalyst and/or activator MgCl2
Binder Acrylic copolymer
Fabric softener Hydrophilic silicone emulsions having density of 1.0 g/cc @20?C
Dispersing agent Condensation product of sulfonated naphthalene with formaldehyde
FIR additive Talc,
Metal oxide: cerium oxide,
Silicate: calcium aluminosilicate
All in different combinations
Non-ionic surfactant Polyoxyethylene alkylphenol ether phosphate
[093] General synthesis for obtaining finished FIR fabric:
[094] The metal oxide was mixed with silicate and/or talc, followed by mixing with non-ionic surfactant in a planetary ball mill using zirconia beads (0.2 to 0.4 mm) for 180 min to obtain the FIR additive suspension. Further, to maintain at least 50% percent wet pick up or retention on the fabric, the FIR additive suspension was diluted to suitable amounts in water and mixed with the finishing formulation comprising to obtain the multifunctional composition. The prepared multifunctional composition was then coated on a textile or fabric using chemical padding machine. The coated textile was then dried at 120°C to 170°C to remove excess water and cured at 140°C to 190°C obtain the finished FIR fabric.
[095] The amounts of various ingredients used in the finished FIR fabric are summarized in Table 1 below.
[096] Table 1: Inventive and comparative examples
Ingredient / Examples Ex. 1 (wt.%) (Comp.) Ex. 2
(wt.%) Ex. 3 (wt.%) Ex. 4 (wt.%) Ex. 5 (wt.%) Ex. 6 (wt.%) Ex. 7 (wt.%) Ex. 8 (wt.%) Ex. 9 (wt.%)
FIR ADDITIVE
*FIR additive
(in wt. ratio) 90:10
T:C 10-40% CAS 80:20
T:C 80:20
CAS:C 80:20
CAS:C 90:10
CAS:C 70:30
CAS:C 80:20
CAS:C 80:20
CAS:C
Non-ionic surfactant 4% 3% 5% 5% 5% 5% 5% 5% 5%
Solid content 60% 60% 60% 60% 60% 60% 60% 60% 60%
MULTIFUNCTIONAL COMPOSITION
FIR additive aqueous suspension 10 10 10 5 7 7 7 2 10
Cross-linking agent 5 5 5 5 5 5 5 5 5
Catalyst and/or activator 1 1 1 1 1 1 1 1 1
Binder 1 1 1 1 1 1 1 1 1
#Fabric softener 10 (SS) 10 (SS) 10 (SS) 10 (SS) 10 (SS) 10 (SS) 10 (SS) 10 (SS) 10 (SS)
Dispersing agent 1 1 1 1 1 1 1 1 1
Remaining being water
*T: talc, C: cerium oxide, CAS: calcium aluminosilicate.
#SS: silicone softener, PS: polyethylene softener.
[097] The fabric employed in various samples that were obtained, as per Table 1, was percale and satin. The finished FIR fabric was tested for various properties, which have been summarized below.
[098] Results and Discussion:
[099] Thermal insulation properties and its durability:
[0100] Thermal insulation testing for finished FIR fabric was done using dry guarded hot plate as per ISO:11092 at NABL accredited labs. The durability of the finish was tested by measuring ash% in different washed samples. Both FIR property and its durability were confirmed up to 75 washes. Results for thermal properties are shown in the form of TOG value. TOG refers to thermal overall grade (1 TOG = 0.1 m2K/W) which is a measure of thermal resistance or insulation/area.
[0101] Finished FIR fabrics were made as per the examples listed in Table 1 and tested for thermal insulation property. Further, the Control Finished fabric was devoid of the FIR additive. The results are summarized in Table 2 below.
[0102] Table 2: Thermal property for Examples 1 to 7
FIR coated fabric Ash, % TOG %TOG increase
Control Finished 0.4 0.146 -
FIR Finished Example 1 1.90 0.169 15.6
FIR Finished Example 2 1.85 0.164 12.5
FIR Finished Example 3 2.81 0.179 22.7
FIR Finished Example 4 1.80 0.170 16.4
FIR Finished Example 5 2.98 0.204 39.8
FIR Finished Example 6 2.91 0.183 25.1
FIR Finished Example 7 2.96 0.213 45.3
[0103] As noted above, the FIR finished fabrics prepared in accordance with the present invention showcase an increase in % ash content and % TOG value. Further, the fabric prepared using (comp.) example 2 showcased the lowest %TOG value, in comparison to other fabric samples.
[0104] The effect of FIR additive loading on finished fabric and TOG value is summarized in Table 3.
[0105] Table 3: Effect of FIR additive loading on thermal property
FIR coated fabric Ash, % TOG %TOG increase
Control Finished 0.4 0.146 -
FIR Finished Example 8 1.0 0.162 9.9
FIR Finished Example 4 1.80 0.170 16.4
FIR Finished Example 5 2.98 0.204 39.8
FIR Finished Example 9 4.20 0.208 42.4
[0106] As noted above, the %TOG value increases with the amount of FIR additive loading.
[0107] The durability of the finished fabric was tested by measuring ash% in different washed samples. Results for durability are shown in the form of % ash content, TOG value and % increase in TOG in Table 4.
[0108] Table 4: Thermal property and durability results at multiple washes
FIR coated fabric Ash, % TOG %TOG increase
Control Finished 0.4 0.146 -
FIR Finished
(based on Example 4) 1.8 0.170 16.4
25 Washed 1.5 0.237 62.3
50 Washed 1.4 0.223 52.7
75 Washed 1.3 0.215 47.3
[0109] As noted above, the finished FIR fabric in accordance with the present invention has a higher TOG value, thereby indicating increased thermal resistance in the finished FIR fabric. Furthermore, despite the fabric being washed multiple times (up to 75 washes), the FIR properties were retained. Therefore, the present invention provides a durable fabric which not only has the FIR properties, but is wrinkle free, acceptable moisture management along with comfort, colorfastness, texture, durability, and resistance to environmental factors. These technical effects are further evident in various tests that were conducted with the finished FIR fabric, as below.
[0110] Far infrared reflective properties:
[0111] Far Infrared Radiation Test was carried out as per GB/T 30127-2013. The finished FIR fabric sample was tested at 34°C and wavelength range ranging between 5µm to 14µm. The emissivity of sample was found to be 0.9 with 2°C rise in the temperature, thereby confirming FIR properties in the sample.
[0112] Wrinkle free property:
[0113] DP (Durable Press) assessment (Wrinkle Free) was tested as per AATCC 124-2014. The finished FIR fabric sample achieved DP of more than 3, thereby indicating wrinkle free or crush-less surface despite multiple washes.
[0114] Moisture management:
[0115] Wicking height measurement was done as per AATCC 197-2013 which confirms moisture management for comfortable use for apparel or bed linens. More than 10 cm wicking height was achieved in 30 minutes, which concludes very good effect of moisture management in the finished FIR fabric.
[001] Advantageously, the FIR additive of the present invention can be used to make a durable finished FIR fabric having key attributes of FIR reflective, wrinkle free, moisture management along with comfort, colorfastness, texture, durability, and resistance to environmental factors.
[0116] The foregoing description of the present invention has been set merely to illustrate the present invention and is not intended to be limiting. Since the modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to the person skilled in the art, the present invention should be construed to include everything within the scope of the disclosure.
[0117] Further, it will be apparent to the person skilled in the art that various changes and modifications may be made without departing from the scope of the present invention as defined in the following claims.

, Claims:WE CLAIM:
1. A far infrared reflective (FIR) additive comprising a mixture of a metal oxide with silicate and/or talc.

2. The additive according to claim 1, wherein the far infrared reflective (FIR) additive is an aqueous suspension comprising the mixture in a non-ionic surfactant.

3. The additive according to claim 1, wherein the metal oxide is selected from Cerium oxide (CeO2), Titanium oxide (TiO2), Zirconium oxide (ZrO2), and Aluminium oxide (Al2O3).

4. The additive according to claim 1, wherein the silicate is selected from silicates of Cerium, Titanium, Zirconium, and Aluminium.

5. The additive according to claim 1, wherein the mixture contains 10 wt.% to 30 wt.% of the metal oxide, and 70 wt.% to 90 wt.% of the silicate and/or talc, the wt.% based on the total weight of the additive.

6. A multifunctional composition comprising:
5.0 wt.% to 15.0 wt.% of at least one cross-linking agent,
0.5 wt.% to 2.0 wt.% of at least one catalyst and/or activator,
1.0 wt.% to 5.0 wt.% of at least one binder,
4.0 wt.% to 12.0 wt.% of at least one fabric softener,
0.5 wt.% to 2.0 wt.% of at least one dispersing agent, and
2.0 wt.% to 10.0 wt.% of at least one far infrared reflective (FIR) additive comprising a mixture of a metal oxide with a silicate and/or talc,
wherein the wt.% is based on the total weight of the composition.

7. The composition according to claim 6, wherein the cross-linking agent is a Methylol dihydroxyethylene urea-based resin.

8. The composition according to claim 6, wherein the catalyst and/or activator is selected from magnesium chloride, magnesium fluoride, magnesium nitrate, sodium acetate, ammonium chloride, zinc nitrate, zinc chloride, and zinc fluoroborate.

9. The composition according to claim 6, wherein the binder is an acrylic binder selected from ethyl acrylate, butyl acrylate, and styrene acrylate.

10. The composition according to claim 6, wherein the fabric softener is a silicone softener selected from ternary blocked hydrophilic silicone emulsions, amino silicones, and quat silicones.

11. The composition according to claim 6, wherein the polyethylene softener is selected from low, medium, and high-density oxidized polyethylene emulsions.

12. The composition according to claim 6, wherein the dispersing agent is selected from acrylic based dispersing agents, naphthalene based dispersing agents, and lignin sulphonate based dispersing agents.

13. A method of applying a multi-functional composition to a fabric comprising the steps of:
(A) coating the fabric with the multi-functional composition comprising:
5.0 wt.% to 15.0 wt.% of at least one cross-linking agent,
0.5 wt.% to 2.0 wt.% of at least one catalyst and/or activator,
1.0 wt.% to 5.0 wt.% of at least one binder,
4.0 wt.% to 12.0 wt.% of at least one fabric softener,
0.5 wt.% to 2.0 wt.% of at least one dispersing agent, and
2.0 wt.% to 10.0 wt.% of at least one far infrared reflective (FIR) additive comprising a mixture of a metal oxide with a silicate and/or talc, to obtain the coated fabric,
wherein the wt.% is based on the total weight of the composition, and
(B) drying and curing the coated fabric at a temperature ranging between 120°C-190°C to obtain a finished FIR fabric having a retention of at least 50% with respect to the infrared reflective (FIR) additive.

14. The method according to claim 13, wherein the finished FIR fabric has multi-functional properties of one or more of thermal insulation, far infrared reflective, wrinkle free, and moisture management.

15. The method according to claim 13, wherein the finished FIR fabric meets the requirements of far infrared radiation in accordance with GB/T 30127-2013, wrinkle free (durable press) in accordance with AATCC 124-2014, moisture management (wicking height) in accordance with AATCC 197-2013.

Dated this 15th day of December 2023

Aditya Birla Science and Technology Company Pvt Ltd.; and
Birla Century (A Division of Century Textiles & Industries Ltd)
By their Agent & Attorney

(Nisha Austine)
of Khaitan & Co
Reg No IN/PA-1390