Formulation and method for carrying out surface and / or finishing treatments on textile substrates suitable to improve the thermal performance thereof, textile product thus treated, object at least partially made from such a textile product, and use of such a formulation to improve the thermal performance of textile substrates

Abstract

The invention relates to a formulation for carrying out surface and / or finishing treatments on textile substrates suitable to improve the thermal performance thereof. Such a formulation comprises : an aqueous colloidal dispersion of hydroxyapatite nanoparticles having the formula Ca10( PO)6(OH)2; at least one polymer binder; at least one fixative, and optionally one or more rheology adjusting additives. The invention further relates to a method for carrying out surface and / or finishing treatments on textile substrates suitable to improve the thermal performance thereof, a textile product thus treated, an object at least partially made from such a textile product, as well as the use of such a formulation to improve the thermal performance of textile substrates.

Description

"FORMULATION AND METHOD FOR CARRYING OUT SURFACE AND / ORFINISHING TREATMENTS ON TEXTILE SUBSTRATES SUITABLE TO IMPROVE THE THERMAL PERFORMANCE THEREOF , TEXTILE PRODUCT THUS TREATED , OBJECT AT LEAST PARTIALLY MADE FROM SUCH A TEXTILE PRODUCT , AND USE OF SUCH A FORMULATION TO IMPROVE THE THERMAL PERFORMANCE OF TEXTILE SUBSTRATES" DESCRIPTIONField of application

[0001] The present invention relates to a formulation and a method for carrying out surface and / or finishing treatments on textile substrates suitable to improve the thermal performance thereof , a textile product thus treated, an obj ect at least partially made from such a textile product , as well as the use of such a formulation to improve the thermal performance of textile substrates . Background art

[0002] In the field of clothing in particular, but also in other fields , the improvement of the thermal performance of textile substrates , generally understood as thermal insulation capacity, is a greatly felt need .

[0003] Such a need has been met in the most varied manners depending on the textile substrate . However, generally, the thermal insulation capacity was obtained by increasing the thickness of the thermal barrier, applying one or more layers of insulating material to the textilesubstrate .

[0004] The disadvantage of such an approach is essentially related to the increase in weight and rigidity of the textile substrate . Therefore , the improvement in thermal performance is generally associated with an alteration of the other features of the textile substrate .

[0005] In this context , the need to improve the thermal performance of a textile substrate by reducing or even eliminating the impact on the other features of the substrate itsel f continues to be felt .Summary of the invention

[0006] Therefore , it is the main obj ect of the present invention to eliminate or at least mitigate the drawbacks of the aforementioned prior art , providing a formulation for making treatment layers on textile substrates which are suitable to improve the thermal performance thereof without af fecting or at least hardly af fecting the other features of the substrate itsel f .

[0007] It is a further obj ect of the present invention to provide a formulation for making treatment layers on textile substrates suitable to improve the thermal performance thereof which can be produced in a cost- ef fective manner .

[0008] It is a further obj ect of the present invention to provide a formulation for making treatment layers ontextile substrates suitable to improve the thermal performance thereof which can be applied in an operatively simple and cost-ef fective manner on a textile substrate .

[0009] It is a further obj ect of the present invention to provide a method for making treatment layers on textile substrates which are suitable to improve the thermal performance thereof without af fecting or at least hardly af fecting the other features of the substrate itsel f .

[0010] It is a further obj ect of the present invention to provide a method for making treatment layers on textile substrates suitable to improve the thermal performance thereof which can be carried out in an operatively simple and cost-ef fective manner on a textile substrate .

[0011] It is a further obj ect of the present invention to provide a textile product which is based on a treated textile substrate and which has improved thermal performance as compared to the untreated textile substrate , without af fecting or at least hardly af fecting the other features of the substrate itsel f .

[0012] It is a further obj ect of the present invention to provide a textile product which has improved thermal performance and can be made in an operatively simple and cost-ef fective manner from a textile substrate .Brief description of the drawings

[0013] The technical features of the invention according to the aforesaid obj ects can be clearly found in the contents of the claims hereinbelow and the advantages thereof will become more apparent from the fol lowing detailed description, given with reference to the accompanying drawings which show one or more embodiments thereof merely given by way of non-limiting example , in which :

[0014] - Figure 1 shows a SEM photograph of a textile product sample made in accordance with the invention;

[0015] - Figure 2 shows a SEM photograph of a textile product sample made not in accordance with the invention, but using HAP micropowders with a particle si ze less than 100 pm;

[0016] - figure 3 shows a photo of a fabric under test and a thermographic image of the test carried out , where the untreated fabric according to the invention is arranged on the left and the treated fabric according to the invention is on the right and in which the surface treated in both cases was on the opposite side of the plate ( external ) .

[0017] - figure 4 shows a photo of a fabric under test and a thermographic image of the test carried out , where the untreated fabric according to the invention is arranged on the left and the treated fabric according to theinvention is on the right and in which the surface treated in both cases was turned towards the plate ( internal ) .

[0018] figures 5 , 6 and 7 show the thermographic images of tests carried out at 50 ° C, 100 ° C and 150 ° C, respectively, where the untreated fabric according to the invention is arranged at the top and the treated fabric according to the invention at the bottom;

[0019] - figure 8 shows the thermographic images of a test carried out on a textile product made according to the invention (bottom image ) and on the same textile product not made according to the invention ( top image ) , both exposed to the irradiation of an infrared lamp placed 1 m away, the textile product according to the invention having a treated side on the face opposite to that exposed to the lamp ; and

[0020] - figure 9 shows the thermographic images of a test carried out on a textile product made according to the invention (bottom image ) and on the same textile product not made according to the invention ( top image ) , both exposed to the irradiation of an infrared lamp placed 1 m away, the textile product according to the invention having a treated side on the face exposed to the lamp .Detailed description

[0021] The present invention relates to a formulation and a method for carrying out surface and / or finishing treatments on textile substrates suitable to improve the thermal performance thereof , a textile product thus treated, an obj ect at least partially made from such a textile product , as well as the use of such a formulation to improve the thermal performance of textile substrates .

[0022] Therefore , the invention will be described by speci fically discussing in sequence :

[0023] - the formulation for carrying out surface and / or finishing treatments on textile substrates suitable to improve the thermal performance thereof ;

[0024] - the method for carrying out surface and / or finishing treatments on textile substrates suitable to improve the thermal performance thereof using the aforesaid formulation;

[0025] - a textile product thus treated;

[0026] - an obj ect at least partially made from such a textile product ;

[0027] - the use of such a formulation to improve the thermal performance of textile substrates .

[0028] " Thermal performance" means the ability to create a temperature di f ference between the two faces of a textile substrate , hereinafter also referred to as the " thermal barrier ef fect" . The higher the temperature di f ference ,the more marked the thermal performance .★ ★ ★

[0029] In accordance with a general embodiment of the invention, the formulation for carrying out surface and / or finishing treatments on textile substrates suitable to improve the thermal performance thereo f , firstly comprises an aqueous colloidal dispersion of hydroxyapatite nanoparticles having the formula Caio ( PO4) 6 ( OH) 2 .

[0030] "Colloidal dispersion" means a mixture of two phases , of which one phase consists of a substance of nanometric dimensions ( diameter between 1 nm and 1 pm) and a continuous dispersing phase .

[0031] Nanoparticles means particles with an average diameter less than 100 nm .

[0032] The formulation further comprises :

[0033] - at least one polymer binder ;

[0034] - at least one fixative ( or crosslinker ) , and

[0035] - optionally one or more rheology adj usting additives .

[0036] The preparation of the formulation, understood as mixing of the components , is based on techniques known per se to those skilled in the textile field, and in particular in the preparation of printing pastes , and therefore will not be described in further detail .

[0037] Advantageously, the formulation according to the invention can be applied to natural , synthetic, arti ficial or mixed textile substrates .

[0038] The term " textile substrates" i s intended to include both woven and non-woven fabrics .

[0039] Natural textile substrates mean substrates consisting of vegetable fibers , fibers of animal origin, or extracted from a mineral .

[0040] Arti ficial textile substrates mean substrates made from natural raw materials which are trans formed into fibers by virtue of chemical processes .

[0041] Synthetic textile substrates mean substrates consisting of fibers derived from synthetic materials , mostly consisting of petroleum derivatives .

[0042] Anticipating at least partially the following description of the method according to the invention, the formulation - once applied to a textile substrate - forms at least one surface treatment layer thereon .

[0043] It was surprisingly possible to veri fy that such at least one treatment layer made with the formulation according to the invention facilitates the propagation of heat in the textile substrate and thus the attainment of a thermal equilibrium .

[0044] It was further surprisingly possible to veri fy that the thermal functional properties of the treatment layercan vary depending on the positioning with respect to the heat source and the main heat transmission mode (by irradiation or by conduction) .

[0045] I f the heat source interacts thermally by irradiation ( e . g . , sunlight ) :

[0046] - when the treatment layer is exposed directly or comes into contact directly with the heat source by irradiation, it spreads the heat over the entire exposed surface acting as a total or partial barrier to di f fusion and dispersion on the opposite surface ;

[0047] - when the treatment layer is not directly exposed by irradiation or does not come into direct contact with the heat source , but is located on the surface opposite to that of heat application, it does not allow the heat to spread on this surface .

[0048] I f the heat source interacts thermally by conduction ( e . g . , body heat ) :

[0049] - when the treatment layer is exposed directly or comes into contact directly with the heat source by conduction, it spreads the heat over the entire exposed surface acting as a total or partial barrier to di f fusion and dispersion on the opposite surface ;

[0050] - when the treatment layer is not directly exposed to or does not come into direct contact with the heat source by conduction, but is located on the surfaceopposite to that of heat application, it does not allow the heat to spread on this surface .

[0051] Operatively, it can be concluded that the treatment layer, once thermal energy is received, tends to trans fer it uni formly and more slowly as compared to the textile substrate to which it is applied .

[0052] This results in an improvement of the thermal properties of the textile substrate , understood as thermal barrier capacity .

[0053] The overall performance of a textile substrate treated with the formulation according to the invention obviously also depends on the material forming the substrate itsel f ( e . g . , wool is per se more insulating than cotton) . However, it has been found that the ef fectiveness of the formulation does not depend on the textile substrate , in the sense that being the substrate equal the presence of the treatment with the formulation has improving ef fects on thermal performance .★ ★ ★

[0054] An essential component of the formulation according to the invention is the aqueous colloidal dispersion of hydroxyapatite nanoparticles having the formula Caio ( PO4) 6 ( OH) 2.

[0055] Hydroxyapatite (HAP ) is a mineral calcium phosphate having the chemical composition Caio ( PO4 ) 6 ( OH) 2 , belongingto the group of apatites. Hydroxyapatite crystals have the shape of a very thin prism with a hexagonal shape. Calcium can also be present in nature in the form Cas (PO4) 3 (OH) (apatite) , which is usually written Caio (PO4) 6 (OH) 2 to highlight that the elementary cell contains two formula units.

[0056] The term apatite commonly refers to certain minerals with the general formula Cas(PO4)3[F, OH, Cl] , while the term hydroxy refers to the anion OH~ . The OH~ group can be replaced by the fluoride ion (F-) , the chloride ion (C1-) or the carbonate (CO2~3) .

[0057] Preferably, hydroxyapatite of formula Caio (PO4) 6 (OH) 2 substantially free of fluorides and chlorides is used in the formulation according to the invention, in order to meet the application requirements in the textile field.

[0058] Hydroxyapatite (HAP) appears as a white solid capable of acquiring grayish, yellow and green or brown tones, but pure hydroxyapatite powder is white. Since it is a crystalline solid, it has high melting points around 1100°C, indicative of strong electrostatic interactions. It is denser than water, with a relative density (with respect to water) of about 3.08 g / cm3and is practically insoluble in water, a property linked to phosphate ions. However, in acidic environments (as in HC1) it is soluble; the solubility is due to the formation of CaC12,a salt highly soluble in water ; moreover, phosphates are protonated (HPO) 42~ and H2PO4- ) and can interact better with water .KNOWN APPLICATIONS OF HAP

[0059] Nanohydroxyapatite ceramics have a variety of applications in bone surgery; in particular, in this field, HAP :

[0060] - is used as a coating for orthopedic and dental prostheses .

[0061] - is a desensiti zing agent used after teeth whitening .

[0062] - is also used as a reminerali zing agent in toothpastes and in the early treatment of cavities .

[0063] Stainless steel and titanium implants are often coated with hydroxyapatite to reduce the rej ection rate thereof .

[0064] HAP is an alternative to allogeneic and xenogenic bone grafts

[0065] HAP is also used in the air filters of motor vehicles to increase the ef ficiency thereof in absorbing and decomposing carbon monoxide ( CO) .

[0066] Applications of HAP which utili ze the thermal properties thereof in flame-retardant / fireproof applications are also known .CHEMICAL AND STRUCTURAL DI FFERENTIATIONS

[0067] Hydroxyapatite (HAP) is part of the apatite class, and based on anionic substitution there can be a wide range of solutions; HAP is naturally occurring, but it can also be produced artificially. Apatites have a general chemical formula Mio2+(XO43~) 6 Z2~ and are frequently non-stoichiometric . M2+ions are doublecharged cations such as Ca2+, Sr2+, Ba2+, Pb2+and Cd2+. The anions XO43~ can be PO43~, AsO43~ , VO43~ , CrO43~ , and MnO43~ , while the monovalent Z present as F ~ , OH~ , Bn , and Cl~ ions have significant differences in crystallography and composition thereof. Similarly, structural and compositional differences can result between natural apatite and synthetic hydroxyapatite, differences can also arise from the production process. It can be synthesized using chemical precursors, in particular calcium and phosphorus, using various methods including dry, wet, thermal methods or a combination of these. HAP can also be extracted from natural sources, such as animal bones and scales, coral, which are rich in HAP content. Different synthesis methods give rise to different morphologies, size and phase crystallinity. SYNTHESIS

[0068] Hydroxyapatite can be synthesized by the reaction of calcium hydroxide with phosphoric acid:

[0069] 10 Ca (OH)2+ 6 H3PO4=> Caio (PO4) e (OH)2+ 18 H2O

[0070] Hydroxyapatite (Caio (PO4) 6 (OH) 2) is expressed by two units of formula Cas(PO4)3OH.

[0071] Similarly, hydroxyapatite can be synthesized through the following reaction:

[0072] 10 Ca (NO3)2.4H2O + 6 NH4H2PO4 => Caio (PO4) 6 (OH) 2 + 20 NH4NO3 + 52 H2O

[0073] Controlling the precipitation rate allows this reaction to generate hydroxyapatite nanoparticles.

[0074] A considerable amount of research on HAP has been devoted to the mechanical properties thereof and to the hydroxyl ions (OH-) located in the center of the Ca2+triangles along the c axes of the hexagonal unit cell. The OH- ions are aligned in columns parallel to the c axis together with the Ca2+and (PO43-) ions. Since the OH- ions within the c axis columns are believed to play an important role in ion conduction, HAP has been considered a one-dimensional anionic conductor.

[0075] Despite the chemical similarity to the mineral component of bone, the peculiar brittleness and low fracture tenacity of HAP has limited the use thereof in applications such as high-load implants. Many methods have been reported for the synthesis of HAP such as solid-state reaction, sol-gel, wet synthesis and hydrothermal methods. The key factors for obtaining controllable proportions and bioactivity are: reactiontemperature, pH and reagent concentration. The properties of HAP, in particular those mentioned above, affect the efficiency of the powder in the final applications thereof. The microstructure of ceramic powders is strongly affected by temperature and synthesis conditions .

[0076] The morphologies (such as nanoparticles, nanowires and nanosheets) of the products could be obtained by adjusting the crystalline nature of the calcium silicate precursors or the phosphate solution type. While by adjusting the chemical compositions of the precursors and the precursor / solution reaction ratio, HAP powders substituted by different types and amounts of elements (such as Si, Na, Mg and Sr, etc.) can be obtained.

[0077] Preferably, the formulation according to the invention uses a colloidal dispersion of HAP nanoparticles obtained with the production process described in the international application W02008007992A2, the content of which is incorporated as reference .Characterization of the technical powders

[0078] HAP powders can be characterized by the following techniques known per se to those skilled in the art:

[0079] A X-ray diffraction (XRD) .

[0080] B Transmission electron microscopy (TEM) studies.

[0081] C Thermal analysis . The thermal behavior of powders has been studied by di f ferential thermal analysis ( DTA) and thermal gravimetric analysis ( TGA)

[0082] D FT- IR spectroscopy .

[0083] E X-ray photoelectron spectroscopy (XPS ) .★ ★ ★

[0084] Preferably, in the formulation according to the invention, the aforesaid aqueous dispersion of hydroxyapatite nanoparticles is from 25% to 40% by weight of said formulation and has a hydroxyapatite concentration between 15% and 16% by weight .

[0085] In particular, the hydroxyapatite nanoparticles are from 3% to 5% by weight of said formulation .

[0086] It was possible to veri fy that with these concentration values , the ef fect of the formulation - in the terms presented above - is particularly accentuated .

[0087] Preferably, the hydroxyapatite nanoparticles have a particle distribution around 50 nm .

[0088] It was experimentally veri fied that the nanometric si ze of the HAP particles is essential for obtaining the ef fects described above .

[0089] Preferably, said at least one polymer binder is from 25% to 40% by weight of said formulation .

[0090] In particular, said at least one polymer binder can be based on acrylic resin, vinyl resin, polyurethaneresin, butadiene resin or mixtures thereof .

[0091] Preferably, the formulation uses polyurethane resins as the polymer binder . Such a choice is linked to the breathable properties of polyurethane resin, an important feature in textile applications ( see in particular, sports-wear garments ) .

[0092] It was possible to veri fy that the choice of binder did not signi ficantly af fect the performance of the formulation .

[0093] Preferably, said at least one fixative ( or crosslinker ) is from 2 % to 5% by weight of said formulation . The fixative is chosen according to the polymer binder present in the formulation .

[0094] Preferably, said one or more rheology adj usting additives are from 15% to 45% by weight of said formulation .

[0095] In particular, said one or more rheology adj usting additives can comprise at least one wetting agent .

[0096] In particular, said one or more rheology adj usting additives can comprise at least one emulsi fying agent .

[0097] In particular, said one or more rheology adj usting additives can comprise :

[0098] - at least one thickening agent ; and

[0099] - at least one pH adj uster ( suitable to trigger the thickening agent ) .

[0100] In accordance with a preferred embodiment of the invention, the formulation consists of :

[0101] - from 25% to 40% by weight of said aqueous dispersion of hydroxyapatite nanoparticles , with a hydroxyapatite concentration between 15% and 16% by weight ( of the aqueous dispersion) ;

[0102] - from 25% to 40% by weight of said at least one polymer binder ;

[0103] - from 2 % to 5% by weight of said at least one fixative ,

[0104] - from 15% to 45% by weight of said one or more rheology adj usting additives ,

[0105] - the rest being water .

[0106] Below is an example of a formulation according to the invention, used in the experimental tests which will be presented in the following of the present description :

[0107] - 30% by weight of aqueous dispers ion of hydroxyapatite nanoparticles , with a concentration of hydroxyapatite between 15% and 16% by weight .

[0108] - 37 % by weight of polyurethane resin (polymer binder ) ;

[0109] - 3% by weight of fixative (blocked polyurethane ) ,

[0110] - 12 % by weight of at least one wetting agent(diol ( s ) ) ;

[0111] - 8% by weight of at least one emulsifying agent ( silicone ( s ) ) .

[0112] - 6.5% by weight of at least one thickening agent (polyurethane; polyacrylate) ; and

[0113] - 0.5% of at least one pH adjuster (amine) ;

[0114] - 3% by weight of water.

[0115] All the weight % of the indicated components comprise solvents and / or water.

[0116] Advantageously, the viscosity of the formulation is chosen based on the application technique to the textile substrate.

[0117] In particular, the formulation can have a viscosity between 25,000 and 50,000 cPs measured with Brookfield viscometer at 20°C, preferably between 30,000 and 40,000 cPs. In this case, the formulation is suitable for application to a textile substrate by frame or cylinder printing.

[0118] In particular, the formulation can have a viscosity between 80,000 and 130,000 cPs measured with Brookfield viscometer at 20°C, preferably between 90,000 and 110,000 cPs. In this case, the formulation is suitable for application to a textile substrate by screen printing .

[0119] In particular, the formulation can have aviscosity between 10,000 and 20,000 cPs measured withBrookfield viscometer at 20°C, preferably between 12,000 and 18,000 cPs. In this case, the formulation is suitable for application to a textile substrate by coating.

[0120] In particular, the formulation can have a viscosity between 300 and 2,000 cPs measured with Brookfield viscometer at 20°C. In this case, the formulation is suitable for application to a textile substrate by a finishing treatment.

[0121] Preferably, the formulation is transparent once applied. Advantageously, however, the formulation can be pigmented .★ ★ ★

[0122] The present invention also relates to a method for carrying out surface and / or finishing treatments on textile substrates suitable to improve the thermal performance thereof.

[0123] In accordance with a general embodiment of the invention, the method comprises the following operating steps :

[0124] a) providing a textile substrate;

[0125] b) providing a predefined amount of the formulation according to the invention and in particular as described above;

[0126] c) optionally, mixing said formulation amountwith a finishing base according to predefined ratios , obtaining a mixture .

[0127] The textile finishing base can consist , for example , of a pigment base or of titanium or white fillers . Preferably, the textile finishing base in the mixture is from 3% to 5% by weight .The method further comprises step d) of applying said formulation or said mixture to said textile substrate by frame printing, cylinder printing, screen printing, coating or finishing treatment , obtaining a semi- finished textile product .

[0128] Depending on the application technique used, the penetration depth of the formulation in the thickness of the textile substrate varies .

[0129] Advantageously, the textile substrate can be natural , synthetic, arti ficial or mixed . The term " textile substrates" is intended to include both woven and non-woven fabrics .

[0130] The semi- finished textile product consists of said textile substrate provided with at least one layer of said formulation or said mixture .

[0131] Such a layer can af fect part of the thickness of said textile substrate at at least one side thereof ; in this case there is a surface treatment in which only one layer of the textile substrate is treated with theformulation; this is referred to as a treated surface layer .

[0132] Alternatively, such a layer can af fect the entire thickness of the textile substrate ; in other words , the treatment layer extends from one side of the textile substrate to the other . In this case there is a finishing treatment in which the entire thickness of the textile substrate is treated with the formulation .

[0133] The semi- finished textile product can also consist of said textile substrate provided with two distinct layers of said formulation or said mixture . This occurs i f the formulation has been applied to both sides of the substrate without reaching the center of the substrate itsel f ; in this case there is a surface treatment extended to both sides of the textile substrate ; this is referred to as a double treated surface layer .In order to obtain maximum performance , the layer must extend over the entire surface of the treated face of the textile substrate , regardless of the penetration thickness in the textile substrate .

[0134] However, advantageously, regardless of the penetration thickness into the textile substrate , said formulation can be applied so that said layer extends only to a part of the surface of the treated face of thetextile substrate .

[0135] Preferably, the surface on which said layer extends follows a predefined pattern, preferably continuous without interruptions .

[0136] Partial surface coverage allows obtaining high performance to the extent in which the treated surface is uninterrupted .

[0137] Alternatively, said formulation can be applied so that said layer extends over the entire surface of the treated face of the textile substrate .

[0138] Advantageously, in step d) of application or, possibly, in a dedicated operating step, the formulation can be applied to the textile substrate so as to form a coating layer which is distinct from said textile substrate and associated with one of the two faces of the textile substrate itsel f .

[0139] Such a solution can be applied in particular in the clothing field to produce garments provided with protective membranes ( e . g . , windproof ) .

[0140] The method further comprises the further operating step e ) of heat treating the semi- finished textile product to activate a crosslinking of the polymer binder so as to obtain a finished textile product .

[0141] The crosslinked polymer matrix has two functions :

[0142] - stabilizing the formulation on the textile substrate; and

[0143] - retaining the hydroxyapatite nanoparticles on the textile substrate.

[0144] Operatively, the temperature and times of the heat treatment are established according to the fixative (crosslinker) used and the features of the textile substrate .

[0145] Preferably, the heat treatment is carried out at a temperature between 130°C and 150°C. It will be possible to operate at lower temperatures in case of textile substrates with lower melting points (e.g., polyamides, polypropylene) . In this case, the temperature reduction must be compensated by acting on the type of fixative (crosslinker) .

[0146] Advantageously, the thermal effects obtainable from the treatment with the formulation depend on the extension of the treated surface and not on the absolute amount of formulation applied per se. In other words, the applied formulation weight (g / cm2) can be minimized by maximizing the treated surface. This allows to limit the alterations to the features of the textile substrate (for example, weight, touch, flexibility, breathability) . Therefore, the treatment with the formulation according to the invention has an highly low impact on the textilesubstrate against a signi ficant improvement in the thermal performance thereof .★ ★ ★

[0147] The present invention also relates to a textile product obtained by applying the method for carrying out surface and / or finishing treatments on textile substrates according to the invention .

[0148] Such a textile product comprises :

[0149] - a textile substrate ;

[0150] - a polymer matrix material which is supported by said textile substrate in the form of at least one layer .

[0151] Advantageously, the textile substrate can be natural , synthetic, arti ficial or mixed . The term " textile substrates" is intended to include both woven and non-woven fabrics .

[0152] Such a layer of material can af fect :

[0153] part of the thickness of said textile substrate at at least a first face of the two opposite faces of said textile substrate ; or

[0154] the entire thickness of said textile substrate extending from one face to the other .

[0155] According to the invention, said polymer matrix material comprises hydroxyapatite nanoparticles having formula Caio ( PO4 ) 6 ( OH) 2 .

[0156] Such nanoparticles are uni formly distributed in said layer .

[0157] Preferably, said polymer matrix material at least partially covers the fibers of said textile substrate at said layer .

[0158] The uni form coverage of the fibers by the aforesaid polymer matrix material was observed under a scanning electron microscope .

[0159] More in detail , a textile product sample according to the invention was analyzed under a scanning electron microscope . As can be seen in figure 1 depicting an SEM photograph of such a sample , the textile product has the fibers ( in the treated layer ) covered by a coating solution ( formed by crosslinked binder, HAP nanoparticles and other components ) which is uni form with some scattered tears .

[0160] Such uni form coverage in the form of a coating is not obtained i f the textile product - in a manner contrary to the invention - was made using HAP micropowders with a particle si ze less than 100 pm .

[0161] A textile sample made by treating the same textile substrate with an aqueous solution of microparticles was analyzed under a scanning electron microscope . As can be seen in figure 2 depicting a SEM photograph of such a sample , the textile product hasfibers ( in the treated layer) which do not have a uni form coverage on the surface , but agglomerates of crosslinked binder, HAP microparticles and other components ) with a si ze between 2 and 20 pm, separated from each other .

[0162] The aforesaid layer of polymer matrix material can extend only to a part of the surface of said first face .

[0163] Preferably, the surface on which said layer extends follows a predefined pattern, preferably continuous without interruptions .

[0164] Alternatively, said layer can extend over the entire surface of said first face .

[0165] The aforesaid material can be present :

[0166] - only in one surface layer of said textile substrate ;

[0167] - throughout the thickness of said textile substrate ;

[0168] - in two non-adj acent surface layers .

[0169] Advantageously, said material can also be present in a coating layer which is distinct from said textile substrate and associated with one of the two faces of the textile substrate .

[0170] The textile substrate can be a fabric or a nonwoven fabric .

[0171] The textile substrate can comprise natural ,synthetic, man-made fibers or a mixture thereof .★ ★ ★

[0172] The present invention also relates to an obj ect of which at least one portion is made from the textile product according to the invention and in particular as described above .

[0173] Resuming at least partially the above description, the textile product according to the invention comprises at least one surface treatment layer at at least a first face of the texti le substrate .

[0174] It was surprisingly possible to veri fy that such at least one treatment layer made from the formulation according to the invention facilitates the propagation of heat in the textile substrate and thus the attainment of a thermal equilibrium .

[0175] The thermal functional properties of the treatment layer can vary depending on the positioning with respect to the heat source and the main heat transmission mode (by irradiation or by conduction) .

[0176] I f the heat source interacts thermally by irradiation ( e . g . , sunlight ) :

[0177] - when the treatment layer is exposed directly or comes into contact directly with the heat source by irradiation, it spreads the heat over the entire exposed surface acting as a total or partial barrier to di f fusionand dispersion on the opposite surface ;

[0178] when the treatment layer is not directly exposed to or does not come into direct contact with the heat source by irradiation, but is located on the surface opposite to that of heat application, it does not allow the heat to spread on this surface .

[0179] I f the heat source interacts thermally by conduction ( e . g . , body heat ) :

[0180] - when the treatment layer is exposed directly or comes into contact directly with the heat source by conduction, it spreads the heat over the entire exposed surface acting as a total or partial barrier to di f fusion and dispersion on the opposite surface ;

[0181] when the treatment layer is not directly exposed to or does not come into direct contact with the heat source by conduction, but is located on the surface opposite to that of heat application, it does not allow the heat to spread on this surface .

[0182] Operatively, the treatment layer, once thermal energy is received, tends to trans fer it uni formly and more slowly as compared to the textile substrate to which it is applied .

[0183] This results in an improvement of the thermal properties of the textile substrate , understood as thermal barrier capacity .

[0184] In accordance with a first preferred embodiment of the present invention, said obj ect can be a garment .

[0185] Advantageously, the garment portion made from the textile product according to the invention can be arranged in said garment so that the first face of said textile product is on the outer side of said garment .

[0186] An environmental heat source is assumed to act thermally by irradiation ( sunlight ) . In this case , by virtue of the presence of the textile product according to the invention, the garment can more markedly carry out the function of total or partial barrier to the di f fusion and dispersion of heat on the surface opposite to that on which the textile product is positioned, i . e . , towards the body . Therefore , the garment thus made of fers improved thermal abilities for protection from high environmental temperatures . Applications of the invention are , for example , sportswear or workwear .

[0187] Advantageously, the garment portion made from the textile product according to the invention can be arranged in said garment so that the first face of said textile product is on the inner side of said garment .

[0188] A heat source is assumed to act thermally by conduction (body heat ) .

[0189] In this case , by virtue of the presence of the textile product according to the invention, the garmentallows heat to be spread over the entire exposed surface , acting as a total or partial barrier to di f fusion and dispersion on the opposite surface . The garment thus made of fers improved thermal insulation abilities of the body, useful for improving protection from low environmental temperatures . Applications of the invention are , for example , sportswear or workwear .

[0190] In accordance with an alternative embodiment of the invention, said garment portion is arranged in between the two faces of said garment . Applications of the invention are , for example , in the clothing field as a membrane in "windproof" sports garments or as a lining for j acket interiors .

[0191] In accordance with a second preferred embodiment of the present invention, said obj ect can be a thermal barrier .

[0192] Such an obj ect is made so that the first face of the textile product is the face of said thermal barrier intended to be exposed to heat .

[0193] In this case , by virtue of the presence of the textile product according to the invention, the heat protection properties of the thermal barrier are enhanced, since the textile product helps to counteract the di f fusion and dispersion of heat on the opposite surface , i . e . , towards the area protected by the thermalbarrier .

[0194] Applications of the invention are , for example , sunshade curtains . According to the position of the treatment layer, the curtain can act :

[0195] - as a thermal barrier reducing the thermal contribution of sunlight ( layer facing outwards ) ;

[0196] - radiant surface ( layer facing inwards ) .

[0197] The present invention also relates to the use of hydroxyapatite nanoparticles having the formula Caio ( PO4 ) 6 ( OH) 2 to carry out surface and / or finishing treatments on textile substrates , suitable to facilitate the spread of heat in the textile substrate .

[0198] The above description clari fies the advantages related to the use according to the invention .EXPERIMENTAL TESTS

[0199] Many experimental tests have been conducted so as to veri fy the behavior of a textile product made according to the present invention .TEST No . 1

[0200] A first test was carried out comparing the thermal behavior of :

[0201] - a white stretch polyamide fabric treated by application of a formulation according to the invention in the form of a paste ( fabric A) ; and

[0202] - the same fabric treated by application of thesame formulation lacking, however, the HAP nanoparticles( fabric B) .

[0203] The formulation according to the invention contained 30% by weight of aqueous dispersion of HAP nanoparticles .

[0204] The two formulations were applied to the fabric following the same methodology and with the same design by printing with 54-thread printing frames.

[0205] The heat source was simulated by means of a heating plate set at a temperature of 40°C. The samples were tested by putting the printed side in contact with both the plate and the opposite side.

[0206] Figure 3 shows a photo of the fabric and a thermographic image of the test carried out, where fabric B is arranged on the left and fabric A on the right. The surface treated in both cases was on the opposite side of the plate (external) .

[0207] The following measurements were detected:

[0208] Fabric B, in area Bxl :

[0209] Max 37.1 °C Min 34.7 °C Average 36.1 °C

[0210] Fabric A, in area Bx2 :

[0211] Max 34.8 °C Min 31.2 °C Average 33.1 °C

[0212] Figure 4 shows a photo of the fabric and a thermographic image of the test carried out, where fabric B is arranged on the left and fabric A on the right. Thesurface treated in both cases was facing the plate(internal) .

[0213] The following measurements were detected:

[0214] Fabric B, in area Bxl :

[0215] Max 38.1 °C Min 34.9 °C Average 37 °C

[0216] Fabric A, in area Bx2 :

[0217] Max 35.1 °C Min 32.2 °C Average 33.5 °C

[0218] Tables 1 and 2 show the test data described above with some numerical processing.Table 1Table 2

[0219] From a reading of the data, the following conclusions can be drawn:

[0220] - the textile product according to the invention - independently of the position of the treatedlayer - has significantly higher thermal performance than a similar textile product free of HAP nanoparticle; the temperature difference ensured by the textile product according to the invention is on average greater than 3- 3.5°C; given the temperatures involved (plate at 40°C) this is a very significant difference;

[0221] - the textile product according to the invention behaves differently if the treated layer is directly exposed to the heat source (INTERNAL) with respect to when it is positioned on the side opposite to the heat source.

[0222] - If the treated layer is on the EXTERNAL side, it seems that the temperature dissipates faster than those with measurements with the treated layer on the INTERNAL side.

[0223] Similar tests were carried out on textile products made from different textile substrates (for example, cotton, polyester) , made with different formulation application techniques. The results are comparable to those carried out on polyamide, with an application technique by printing with 54-thread printing frames. The conclusions drawn can thus be generalized. TEST No. 2

[0224] Tests similar to those presented as test no. 1 were carried out on the same fabrics (polyamide) using afoulard technique of applying the formulation (with and without HAP nanoparticles ) , bringing the plate to 50 ° C, 100 ° C and 150 ° C .

[0225] It should be noted that with the foulard technique the treated layer extends throughout the thickness of the textile substrate , from one side to the other .

[0226] Fabric A indicates a white stretch polyamide fabric treated by means of the foulard application technique of a formulation according to the invention in the form of a paste .

[0227] Fabric B indicates the same fabric treated by application of the same formulation lacking, however, the HAP nanoparticles .

[0228] The formulation according to the invention contained 30% by weight of aqueous dispersion of HAP nanoparticles .

[0229] The two formulations were applied to the fabric following the same methodology .

[0230] Figure 5 shows the thermographic images of the test carried out at 50 ° C, where fabric B is arranged at the top and fabric A at the bottom .

[0231] Figure 6 shows the thermographic images of the test carried out at 100 ° C, where fabric B is arranged at the top and fabric A at the bottom .

[0232] Figure 7 shows the thermographic images of the test carried out at 150°C, where fabric B is arranged at the top and fabric A at the bottom.

[0233] The temperature measurements at 50°C, 100°C and 150°C, respectively, with some numerical processing are presented in Tables 3, 4 and 5 below.Table 3Table 4Table 5

[0234] With respect to test no. 1, the textile product is treated throughout the thickness thereof with the formulation according to the invention and no single treatment layer can be identified on either side of the textile product.

[0235] From a reading of the data, the following conclusions can be drawn:

[0236] - the textile product according to the invention has significantly higher thermal performance than a similar textile product free of HAP nanoparticle not so much in terms of maximum temperature (not significant since the temperature is evaluated in direct contact with the heat source) , but rather in terms of minimum temperature which is always lower than fabric B; the difference between minimum temperatures ranges from 2°C (at 50°C) to 15.3°C (at 150°C) ; given the temperatures involved (plate from 50 to 150°C) this is a very significant difference;

[0237] - the heat supplied through the plate is dispersed more quickly by the treated fabric (fabric A) , and the dispersion is proportional to the amount of heat supplied . TEST No. 3

[0238] In vivo tests were carried out on long-sleeved turtleneck sweaters made of 100% polyamide so as to evaluate the thermal-physiological comfort, carried out in a climatic chamber, under controlled environmental and metabolic conditions.

[0239] The sweaters were treated as in test no. 1; in a first group of samples the treated side of the sweateris on the inner face of the sweater, in a second group of samples the treated side of the sweater is on the outer face of the sweater.

[0240] Fabric A is the white stretch polyamide fabric treated with the formulation according to the invention; this sweater has an average dry weight value of 128.8 + / - 11.7 g of standard deviation.

[0241] Fabric B is same fabric treated by application of the same formulation lacking, however, HAP nanoparticles; this sweater an average dry weight value of 128.9 + / - 11.5 g of standard deviation

[0242] The environmental conditions were as follows: air temperature (Ta) 23.4 ± 0.4°C and relative humidity (RHa) 54.4 ± 1.1%.

[0243] During the initial stage of the test, a variable ventilation equal to the walking speed of the Tester was also used, so as to simulate the apparent wind generated with movement. After 20 minutes, the ventilation was stopped in order to increase body heating and consequent sweating.

[0244] Twenty tests were carried out divided as follows :

[0245] - Five tests on fabric A treated on the external side;

[0246] - Five tests on fabric B treated on theexternal side ;

[0247] - Five tests on fabric A treated on the internal side ;

[0248] - Five tests on fabric B treated on the internal side .

[0249] Testers carried out a controlled activity, according to the methods of a predefined "Experimental Protocol" . Each tester carried out the tests , testing the types of sweaters .

[0250] During the tests , the following parameters were acquired :

[0251] - Temperature ( ISO 9886 : 2004 ) and average skin humidity;

[0252] - Temperature and humidity of the microclimate between skin and sweater in the front and rear ;

[0253] - Surface temperature of the sweater in the rear area ;

[0254] - Amount of sweat produced;

[0255] - Amount of residual sweat on the shirt ;

[0256] - Heart rate ;

[0257] - Subj ective sensations related to thermal comfort .

[0258] At each stage of the test , a map of the surface temperature of the sweater was made . The thermographic images on the Testers were acquired every 5 minutes ,identified on the back of the Testers.

[0259] Based on the results of the tests carried out, the following observations can be made:

[0260] - The average skin temperature is significantly lower in the reference sweaters (fabric B) than in the sweaters according to the invention (fabric A) ;

[0261] - The highest average skin humidity is found when wearing the sweater with fabric A (internal print) ;

[0262] - The amount of sweat produced by wearing the different types of sweaters does not show significant differences ;

[0263] - The heart rate while wearing the different types of shirts does not show significant differences;

[0264] - As for subjective sensations, there are no significant differences.

[0265] In conclusion, the most important data are those related to temperatures, where lower values are found when wearing the sweaters of fabric B as compared to those with fabric A, especially with the print on the internal side. Against a higher temperature, a higher humidity on the skin and in the microclimate was also found by wearing the sweater of fabric A with an internal print. However, no significant differences were found in the amounts of sweat produced and residual sweat on the sweaters .

[0266] The results confirm the results of tests 1 and 2 .

[0267] When the side of the substrate treated with the formulation according to the invention is directly exposed to a heat source , the heat is dispersed and di f fused faster and more homogeneously as compared to the same substrate treated without HAP nanoparticles .TEST No . 4

[0268] A further test was carried out comparing the thermal behavior of :

[0269] a polyester treated by application of a formulation according to the invention in the form of a paste ( fabric A) ; and

[0270] - the same fabric treated by application of the same formulation lacking, however, the HAP nanoparticles ( fabric B ) .

[0271] The formulation according to the invention contained 30% by weight of aqueous dispersion of HAP nanoparticles .

[0272] The two formulations were applied to the fabric by coating, forming a 20 pm (micron) layer .

[0273] The heat source was simulated by an IR 300W lamp placed at a distance of Im . The heat source acts by irradiation . The samples were tested by placing the coated side both in the position opposite to that ofexposure (see figure 8) , and in a position directly exposed to the lamp (see figure 9) .

[0274] Figure 8 shows the thermographic images of the test carried out on fabric A (bottom image) and on fabric B (top image) , both positioned with the coated side on the face directly exposed to the lamp on the face opposite to that exposed to the lamp.

[0275] The temperature measurements are shown in table6 below:Table 6

[0276] Figure 9 shows the thermographic images of the test carried out on fabric A (bottom image) and on fabric B (top image) , both positioned with the coated side on the face opposite to that exposed to the lamp.

[0277] The temperature measurements are shown in table 7 below:Table 7

[0278] From a reading of the data, the following conclusions can be drawn :

[0279] the textile product according to the invention - regardless of the position of the treated layer - has signi ficantly di f ferent thermal performance than a similar textile product lacking HAP nanoparticles in terms of both maximum and minimum temperature ;

[0280] - the textile product according to the invention ( fabric A) behaves di f ferently i f the treated layer is directly exposed to the heat source (EXTERNAL coating) with respect to when it is positioned on the side opposite to the heat source ( INTERNAL coating) .

[0281] - I f the treated layer is on the EXTERNAL side( i . e . , facing the heat source ) , higher temperatures are observed with respect to when the treated layer is on the internal side ; it seems that the heat is dissipated more quickly than in the case with the treated layer on the INTERNAL side .

[0282] The invention provides several advantages , some of which have already been described .

[0283] Therefore , the invention thus devised achieves the pre-set purposes .

[0284] The formulation according to the invention allows to make treatment layers on textile substrateswhich improve the thermal performance thereof without af fecting or at least hardly af fecting the other features of the substrate itsel f .

[0285] The formulation according to the invention is cost-ef fectively producible .

[0286] The formulation according to the invention can be applied in an operatively simple and cost-ef fective manner to a textile substrate , using techniques well known in the textile field per se .

[0287] The method according to the invention allows to make treatment layers on textile substrates suitable to improve the thermal performance thereof without af fecting or at least hardly af fecting the other features of the substrate itsel f .

[0288] The method according to the invention can be carried out in an operatively simple and cost-ef fective manner on a textile substrate .

[0289] The textile product according to the invention has improved thermal performance as compared to the untreated textile substrate , and has substantially unchanged or hardly altered the other features of the substrate itsel f .

[0290] The textile product according to the invention can be made in an operatively simple and cost-ef fective manner starting from a textile substrate .

[0291] Obviously, in the practical embodiment thereof, it may also take different shapes and configurations from that disclosed above, without departing from the present scope of protection.

[0292] Moreover, all details may be replaced by technically equivalent elements, and any size, shape, and material may be used according to needs.

Claims

CLAIMS1. A formulation for carrying out surface and / or finishing treatments on textile substrates suitable to improve the thermal performance thereof, characterized in that it comprises: an aqueous colloidal dispersion of hydroxyapatite nanoparticles having the formula Caio (PO4) 6 (OH) 2;- at least one polymer binder;- at least one fixative, and- optionally one or more rheology adjusting additives.

2. A formulation according to claim 1, wherein said aqueous dispersion of hydroxyapatite nanoparticles is from 25% to 40% by weight of said formulation and has a hydroxyapatite concentration between 15% and 16% by weight .

3. A formulation according to claim 1 or 2, wherein the hydroxyapatite nanoparticles are from 3% to 5% by weight of said formulation.

4. A formulation according to claim 1, 2 or 3, wherein the hydroxyapatite nanoparticles have a particle distribution around 50 nm.

5. A formulation according to any one of the preceding claims, wherein said at least one polymer binder is from 25% to 40% by weight of said formulation.

6. A formulation according to any one of the precedingclaims, wherein said at least one polymer binder is based on acrylic resin, vinyl resin, polyurethane resin, butadiene resin or mixtures thereof.

7. A formulation according to any one of the preceding claims, wherein said at least one fixative is from 2% to 5% by weight of said formulation.

8. A formulation according to any one of the preceding claims, wherein said one or more rheology adjusting additives are from 15% to 45% by weight of said formulation .

9. A formulation according to any one of the preceding claims, consisting of:- from 25% to 40% by weight of said aqueous dispersion of hydroxyapatite nanoparticles, with a hydroxyapatite concentration between 15% and 16% by weight.- from 25% to 40% by weight of said at least one polymer binder .- from 2% to 5% by weight of said at least one fixative,- from 15% to 45% by weight of said one or more rheology adjusting additives,- the rest being water.

10. A formulation according to any one of the preceding claims, wherein said one or more rheology adjusting additives comprise at least one wetting agent.

11. A formulation according to any one of thepreceding claims, wherein said one or more rheology adjusting additives comprise at least one emulsifying agent .

12. A formulation according to any one of the preceding claims, wherein said one or more rheology adjusting additives comprise:- at least one thickening agent; and- at least one pH adjuster.

13. A formulation according to any one of the preceding claims, having a viscosity between 25,000 and 50,000 cPs measured with Brookfield viscometer at 20°C, preferably between 30,000 and 40,000 cPs, and is suitable for application to a textile substrate by frame or cylinder printing.

14. A formulation according to any one of claims 1 to 12, having a viscosity between 80,000 and 130,000 cPs measured with Brookfield viscometer at 20°C, preferably between 90,000 and 110,000 cPs, and is suitable for application to a textile substrate by screen printing.

15. A formulation according to any one of claims 1 to 12, having a viscosity between 10,000 and 20,000 cPs measured with Brookfield viscometer at 20°C, preferably between 12,000 and 18,000 cPs, and is suitable for application to a textile substrate by coating.

16. A formulation according to any one of claims 1to 12 , having a viscosity between 300 and 2 , 000 cPs measured with Brookfield viscometer at 20 ° C and is suitable for application to a textile substrate by a finishing treatment .17 . A method for carrying out surface and / or finishing treatments on textile substrates suitable to improve the thermal performance thereof , comprising the following operating steps : a ) providing a textile substrate ; b ) providing a predefined amount of the formulation according to one or more of the preceding claims ; c ) optionally, mixing said formulation amount with a textile finishing base according to predefined ratios , obtaining a mixture ; d) applying said formulation or said mixture to said textile substrate by frame printing, cylinder printing, screen printing, coating or finishing treatment , obtaining a semi- finished textile product , consisting of said textile substrate provided with a layer of said formulation or said mixture which af fects part of the thickness of said textile substrate at at least one face thereof or which af fects the entire thickness thereof ; e ) heat treating the semi- finished textile product to activate a crosslinking of the polymer binder so as to obtain a finished textile product .18 . A textile product comprising :- a textile substrate ;- a polymer matrix material which is supported by said textile substrate in the form of at least one layer af fecting part of the thickness of said textile substrate at at least a first face of the two opposite faces of said textile substrate or af fecting the entire thickness of said textile substrate extending from one face to the other, characterized in that said polymer matrix material comprises hydroxyapatite nanoparticles having formula Caio ( PO4 ) 6 ( OH) 2 and wherein said nanoparticles are uni formly distributed in said layer .19 . A textile product according to claim 18 , wherein said polymer matrix material covers at least partially the fibers of said textile substrate at said layer .20 . A textile product according to claim 18 or 19 , wherein said layer extends only to a part of the surface of said first face .21 . A textile product according to claim 20 , wherein the surface on which said layer extends follows a predefined pattern, preferably continuous without interruptions .22 . A textile product according to any one ofclaims 18 to 21, wherein said layer extends over the entire surface of said first face.

23. A textile product according to any one of claims 18 to 22, wherein said material is present only in a surface layer of said textile substrate.

24. A textile product according to any one of claims 18 to 22, wherein said material is present throughout the thickness of said textile substrate.

25. A textile product according to any one of claims 18 to 22, wherein said material is present in two surface layers which are not adjacent to each other.

26. A textile product according to any one of claims 18 to 25, wherein said material is also present in a coating layer which is distinct from said textile substrate and associated with one of the two faces of the textile substrate.

27. A textile product according to any one of claims 18 to 26, wherein said textile substrate is a fabric or a non-woven fabric.

28. A textile product according to claim 27, wherein said textile substrate comprises natural, synthetic, artificial fibers or a mixture thereof.

29. An object characterized in that at least one portion of said object is made from the textile product according to one or more of claims 18 to 28.

30. An object according to claim 29, wherein said object is a garment.

31. An object according to claim 30, wherein said garment portion is arranged in said garment so that the first face of said textile product is located on the external side of said garment.

32. An object according to claim 30, wherein said garment portion is arranged in said garment so that the first face of said textile product is located on the internal side of said garment.

33. An object according to claim 30, wherein said garment portion is arranged in between the two faces of said garment.

34. An object according to claim 29, wherein said object is a thermal barrier and wherein said first face of the textile product is the face of said thermal barrier intended to be exposed to heat.

35. Use of hydroxyapatite nanoparticles having the formula Caio (PO4) 6 (OH) 2 to carry out surface and / or finishing treatments on textile substrates, which facilitate the spread of heat in the textile substrate.

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