WO2012046039A2

WO2012046039A2 - Textile having a camouflage pattern thereon

Info

Publication number: WO2012046039A2
Application number: PCT/GB2011/051882
Authority: WO
Inventors: Warrick James David Allen; Andrea Duffy; Nicholas Horrocks; Elizabeth Lakin; James Leonard Rolfe
Original assignee: Novel Polymer Solutions Limited
Priority date: 2010-10-04
Filing date: 2011-10-04
Publication date: 2012-04-12
Also published as: GB201016670D0; WO2012046039A3

Abstract

According to the invention there is provided a textile having a camouflage pattern thereon including: a textile piece having a polymeric coating; and one or more light absorbing substances which are adhered to the polymeric coating so as to form a camouflage pattern, in which the polymeric coating includes a polymer formed by polymerising a polymeric precursor which includes a group of sub-Formula (I) (Formula (I)) where R² and R³ are independently selected from (CR⁷R⁸)_n, or a group CR⁹R¹⁰, CR⁷R⁸CR⁹R¹⁰ or CR⁹R¹⁰CR⁷R⁸ where n is 0, 1 or 2, R⁷ and R⁸ are independently selected from hydrogen, halo or hydrocarbyl, and either one of R⁹ or R¹⁰ is hydrogen and the other is an electron withdrawing group, or R⁹ and R¹⁰ together form an electron withdrawing group; and R⁴ and R⁵ are independently selected from CH or CR¹¹ where R¹¹ is an electron withdrawing group, the dotted lines indicate the presence or absence of a bond, X¹ is a group CX²X³ where the dotted line bond to which it is attached is absent and a group CX² where the dotted line bond to which it is attached is present, Y¹ is a group CY²Y³ where the dotted line bond to which it is attached is absent and a group CY² where the dotted line bond to which it is attached is present, and X², X³, Y² and Y³are independently selected from hydrogen, fluorine or other substituents, R¹ is selected from hydrogen, halo, nitro, hydrocarbyl, optionally substituted or interposed with functional groups, or (Formula (II)); and R¹³is C(O) or S(O)₂.

Description

Textile having a camouflage pattern thereon

This invention relates to a textile having a camouflage pattern thereon, and to methods of producing same.

There is a well-known need to provide textiles having a camouflage pattern for a number of applications and uses. This not only includes military application but also for civilian use such as civil defence and outdoor pursuits (e.g. hunting, fishing and wildlife watching). Visible camouflage patterns are provided with the intention of enabling a wearer to avoid visual observation, and the generalised camouflage strategies for achieving this are well established. Typically, a camouflage strategy is adopted in order to break up the outline of the camouflaged person and to match the camouflaged person with the intended background, or at least to minimise the observable differences. It will be apparent that visible camouflage relates to camouflage patterns which are effective in the visible region of the electromagnetic spectrum. More recently, sensor systems enabling enhanced observation outside the visible spectral regions have become more widespread e.g. through the use of 'night vision' systems and thermal imagers to see in the dark using infra-red radiation. This has led to a need for camouflage patterns which are effective over these spectral regions of the electromagnetic spectrum (hereinafter the term

"camouflage patterns' is used to generically to describe camouflage techniques across the visible and infrared regions).

As well as matching the spectral properties a practical and commercially useful camouflage textile would generally be expected to match acceptable standards for: durability, comfort, light- fastness, wash-fastness and flame retardancy. There is an on-going need to provide camouflage textiles which have acceptable properties across all these requirements.

A particular problem relates to the fixing of dyes onto polyaramid

(hereinafter termed 'aramid') textiles and to other coating processes involving such textiles, since it is very difficult to obtain adhesion onto aramid fibres. Aramid fibres are well known for possessing excellent impact absorption properties and strength, and are employed in a variety of applications which use these excellent properties, such as in military uniforms, and other items of clothing where it is desired to employ a camouflage pattern. Therefore, there is a particular need for the provision of textiles containing aramids or other flame retardant fibres having a camouflage pattern, but also there is a particular problem associated with this need.

The present invention, in at least some of its embodiments, addresses some or all of the above described problems and needs.

According to a first aspect of the invention there is provided a textile having a camouflage pattern thereon including:

a textile piece having a polymeric coating; and

one or more light absorbing substances which are adhered to the polymeric coating so as to form a camouflage pattern,

in which the polymeric coating includes a polymer formed by polymerising a polymeric precursor which includes a group of sub-formula (I)

R

[ I ]

where R² and R³ are independently selected from (CR⁷R⁸)_n, or a group CR⁹R¹⁰, CR⁷R⁸CR⁹R¹⁰ or CR⁹R¹⁰CR⁷R⁸ where n is 0, 1 or 2, R⁷ and R⁸ are independently selected from hydrogen, halo or hydrocarbyl, and either one of R⁹ or R ⁰ is hydrogen and the other is an electron withdrawing group, or R⁹ and R¹⁰ together form an electron withdrawing group; and

R⁴ and R⁵ are independently selected from CH or CR¹¹ where R¹¹ is an electron withdrawing group, the dotted lines indicate the presence or absence of a bond, X¹ is a group CX²X³ where the dotted line bond to which it is attached is absent and a group CX² where the dotted line bond to which it is attached is present, Y¹ is a group CY²Y³ where the dotted line bond to which it is attached is absent and a group CY² where the dotted line bond to which it is attached is present, and X², X³, Y² and Y³ are independently selected from hydrogen, fluorine or other substituents,

R¹ is selected from hydrogen, halo, nitro, hydrocarbyl, optionally substituted

D³ p⁵-—-γ¹

or interposed with functional groups, or ^ — ¹ , and

R¹³ is C(0) or S(0)₂.

International publications WO00/06610, WO00/06533, WO00/06658 and WO01/40874, the contents of all of which are herein incorporated by reference, disclose a wide range of polymers of the dienyl type, corresponding monomers, and methods for preparing the polymers and monomers. Some of the polymers described in these publications correspond to polymers which might be used in the present invention. However, these publications do not even suggest that textiles might be coated to enable a camouflage pattern to be produced.

For the avoidance of doubt, the term 'polymeric precursor' includes reference to monomers, and also to pre-polymers obtained by partial or pre- polymerisation of one or more monomers.

In many embodiments, a visible camouflage pattern is provided. In these embodiments, at least one light absorbing substance absorbs visible light, and is adhered to the polymeric coating to provide the visible camouflage pattern.

In some embodiments, at least one light absorbing substance absorbs infra-red radiation, and is adhered to the polymeric coating to provide an infrared camouflage pattern. WO95/06850 discloses that carbon based pigments such as carbon black and chitin resins may be used as infra-red absorbing pigments to form an infra-red camouflage pattern. Other substances known to the skilled reader as infra-red absorbing substances suitable for use in infra-red camouflage may be used. An infra-red camouflage pattern may be provided in addition to a visible camouflage pattern, although it is possible also to provide a textile which has an infra-red camouflage pattern and no visible camouflage pattern.

Typically, the light absorbing substances are selected so as to provide as part of the camouflage pattern at least one colour selected from beige, brown, tan, sand, black and khaki. Other colours, such as green or olive drab, may be used as required for any specific application. The camouflage pattern can be of any desired type, such as woodland, artic or desert. Typically, the camouflage pattern includes at least two areas of differing colours (or spectral reflectivity).

In some preferred embodiments, at least one light absorbing substance is a dye, and the polymeric coating acts to promote adhesion of the dye to the textile piece. It is highly advantageous that aramid containing textiles may be dyed in this manner.

The dye may be an acid dye or a basic dye. Adhesion to acid and basic dyes can be advantageously enhanced by the provision of one or more suitable functional groups within the polymeric precursor. For example, an amine moiety may be advantageously used in conjunction with acid dyes, and a carboxyl substituent may be advantageously used in conjunction with a basic dye. Without wishing to be bound by any one particular theory or conjecture, it is believed that the presence of these functional groups allows bonding or another interaction to occur between the functional group and the dye. The use of other types of dye is within the scope of the invention. Furthermore, the invention is not limited to bonding or interactions between the function group and the dye. For example, it is envisaged that dyes may be retained on textile fibres through other mechanisms, such as diffusion into the polymeric structure of the coating.

In other preferred embodiments, at least one light absorbing substance is a pigment contained in a binder, and the polymeric coating acts to promote adhesion to the binder and/or pigment to the textile piece. Binders and pigments which are well known in the art may be used. For example, carbon black may be used as a pigment. It is known from eg WO95/06850 that pigments such as carbon black can be used to form an infra-red camouflage pattern. Many other pigments and binders would readily suggest themselves to the skilled reader. It is possible to use a binder containing one or more dyes.

The textile piece may be a plain, uncoloured textile. Alternatively, and advantageously, the textile piece beneath the polymeric coating may be pre- coloured with one or more pre-colouring light absorbing substances. It is understood that such pre-colouring light absorbing substances are present on the textile piece prior to coating with the polymeric coating, and therefore are situated underneath the polymeric coating. An advantage with using a pre- coloured textile piece is that it reduces the complexity and expense of the subsequent step in which light absorbing substances are adhered onto the polymeric coating. The polymeric coating of the invention can adhere well to pre- coloured textile pieces as well as to plain, uncoloured textile pieces.

The textile piece may include synthetic fibres. Examples of synthetic textile fibres which may be coated in accordance with the invention are aramid, nylon and polyester. The treatment of natural fibres is also in the scope of the invention.

It is particularly advantageous that camouflage patterns can be formed on textile pieces containing aramid fibres. The textile piece may be formed entirely from aramid fibres, or may be formed from a mixture of aramid fibres and fibres of at least one other kind. The aramid fibres may be meta-aramid fibres and/or para-aramid fibres. Examples of suitable aramid fibres are Kevlar (RTM), Kermel (RTM) and Twaron (RTM). Examples of mixtures of aramid fibres with fibres of another kind or kinds include various mixtures of aramid fibres with viscose fibres, which may be flame retardant (FR) viscose fibres. Blends such as a 50% aramid/ 50% FR viscose blend or a mixture of para-aramid, rayon and

polybenzimidazole fibres may be used.

According to a second aspect of the invention there is provided a method of producing a textile having a camouflage pattern thereon including the steps of:

providing a polymeric precursor which includes a group of sub-formula (I)

—

where R² and R³ are independently selected from (CR⁷R⁸)_n, or a group CR⁹R¹⁰, CR⁷R⁸CR⁹R¹⁰ or CR⁹R¹⁰CR⁷R⁸ where n is 0, 1 or 2, R⁷ and R⁸ are

independently selected from hydrogen, halo or hydrocarbyl, and either one of R⁹ or R¹⁰ is hydrogen and the other is an electron withdrawing group, or R⁹ and R¹⁰ together form an electron withdrawing group, and

R⁴ and R⁵ are independently selected from CH or CR¹¹ where R¹¹ is an electron withdrawing group, the dotted lines indicate the presence or absence of a bond, X¹ is a group CX²X³ where the dotted line bond to which it is attached is absent and a group CX² where the dotted line bond to which it is attached is present, Y¹ is a group CY²Y³ where the dotted line bond to which it is attached is absent and a group CY² where the dotted line bond to which it is attached is present, and X², X³, Y² and Y³ are independently selected from hydrogen, fluorine or other substituents, R¹ is selected from hydrogen, halo, nitro, hydrocarbyl, optionally

R³ R⁵ Y¹

substituted or interposed with functional groups, or *·· · , and

R¹³ is C(O) or S(0)₂; providing a textile piece;

coating the textile piece with the polymeric precursor;

polymerising the polymeric precursor so as to produce a polymeric coating on the textile piece; and

adhering one or more light absorbing substances to the polymeric coating so as to form a camouflage pattern.

Preferably, the polymeric precursor is polymerised by exposure to ultraviolet radiation. Alternative polymerisation methods include the application of heat (which may be in the form of IR radiation), where necessary in the presence of an initiator, by the application of other sorts of initiator such as chemical initiators, or by initiation using an electron beam. The expression "chemical initiator" as used herein refers to compounds which can initiate polymerisation such as free radical initiators and ion initiators such as cationic or anionic initiators as are understood in the art. In the preferred embodiments in which the monomer is polymerised by exposure to ultraviolet radiation, polymerisation may take place either spontaneously or in the presence of a suitable initiator. Examples of suitable initiators include 2, 2' - azobisisobutyronitrile (AIBN), aromatic ketones such as benzophenones in particular acetophenone; chlorinated acetophenones such as di- or tri- chloracetophenone; dialkoxyacetophenones such as dimethoxyacetophenones (sold under the trade name "Irgacure 651") dialkylhydroxyacetophenones such as dimethylhydroxyacetophenone (sold under the trade name "Darocure 1173"); substituted dialkylhydroxyacetophenone alkyl ethers such compounds of formula

where R^y is alkyl and in particular 2, 2-dimethylethyl, R^x is hydroxyl or halogen such as chloro, and R^p and R^q are independently selected from alkyl or halogen such as chloro (examples of which are sold under the trade names "Darocure 1 1 16" and "Trigonal P1"); 1-benzoylcyclohexanol-2 (sold under the trade name "Irgacure 184"); benzoin or derivatives such as benzoin acetate, benzoin alkyl ethers in particular benzoin butyl ether, dialkoxybenzoins such as dimethoxybenzoin or deoxybenzoin; dibenzyl ketone; acyloxime esters such as methyl or ethyl esters of acyloxime (sold under the trade name "Quantaqure PDO"); acylphosphine oxides, acylphosphonates such as dialkylacylphosphonate, ketosulphides for example of formula

where R^z is alkyl and Ar is an aryl group; dibenzoyl disulphides such as 4, 4'- dialkylbenzoyldisulphide; diphenyldithiocarbonate; benzophenone; 4, 4'-bis (N, N-dialkyamino) benzophenone; fluorenone; thioxanthone; benzil; or a compound of formula

where Ar is an aryl group such as phenyl and R^z is alkyl such as methyl (sold under the trade name "Speedcure BMDS").

As used herein, the term "alkyl" refers to straight or branched chain alkyl groups, suitably containing up to 20 and preferably up to 6 carbon atoms. The terms "alkenyl" and "alkynyl" refer to unsaturated straight or branched chains which include for example from 2-20 carbon atoms, for example from 2 to 6 carbon atoms. Chains may include one or more double to triple bonds respectively. In addition, the term "aryl" refers to aromatic groups such as phenyl or naphthyl.

The term "hydrocarbyl" refers to any structure comprising carbon and hydrogen atoms. For example, these may be alkyl, alkenyl, alkynyl, aryl such as phenyl or napthyl, arylalkyl, cycloalkyl, cycloalkenyl or cycloalkynyl. Suitably they will contain up to 20 and preferably up to 10 carbon atoms. The term "heterocylyl" includes aromatic or non-aromatic rings, for example containing from 4 to 20, suitably from 5 to 10 ring atoms, at least one of which is a heteroatom such as oxygen, sulphur or nitrogen. Examples of such groups include furyl, thienyl, pyrrolyl, pyrrolidinyl, imidazolyl, triazolyl, thiazolyl, tetrazolyl, oxazolyl, isoxazolyl, pyrazolyl, pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, quinolinyl, isoquinolinyl, quinoxalinyl, benzthiazolyl, benzoxazolyl, benzothienyl or benzofuryl.

The term "functional group" refers to reactive groups such as halo, cyano, nitro, oxo, C(0)_nR^a, OR^a, S(0)_tR^a, NR^bR^c, OC(0)NR^bR^c, C(0)NR^bR^c, OC(O) NR^bR^c, -NR⁷C(O)_nR⁶, -NR^aCONR^bR^c, - C=NOR^a, -N=CR^bR^c, S(0)_tNR^bR^c, C(S)_nR^a, C(S)OR^a, C(S)NR^bR^c or - NR^bS(O)_tR^a where R^a, R^b and R^c are independently selected from hydrogen or optionally substituted hydrocarbyl, or R^b and R° together form an optionally substituted ring which optionally contains further heteroatoms such as S(0)_s, oxygen and nitrogen, n is an integer of 1 or 2, t is 0 or an integer of 1 -3. In particular, the functional groups are groups such as halo, cyano, nitro, oxo, C(0)_nR^a, OR^a, S(0)_tR^a, NR^bR^c, OC(0)NR^bR^c, C(0)NR^bR°, OC(O)NR^bR^c, -NR⁷C(0)_nR⁶, -NR^aCONR^bR^c, - NR^aCSNR^bR^c, C=NOR^a, -N=CR^bR^c, S(0)_tNR^bR°, or -NR^bS(0)_tR^a where R^a, R^b and R^c , n and t are as defined above.

The term "heteroatom" as used herein refers to non-carbon atoms such as oxygen, nitrogen or sulphur atoms. Where the nitrogen atoms are present, they will generally be present as part of an amino residue so that they will be substituted for example by hydrogen or alkyl.

The term "amide" is generally understood to refer to a group of formula C(0)NR^aR^b where R^a and R^b are hydrogen or an optionally substituted hydrocarbyl group. Similarly, the term "sulphonamide" will refer to a group of formula S(0)₂NR^aR^b. Suitable groups R^a include hydrogen or methyl, in particular hydrogen.

The nature of any electron withdrawing group or groups additional to the amine moiety used in any particular case will depend upon its position in relation to the double bond it is required to activate, as well as the nature of any other functional groups within the compound. The term "electron withdrawing group" includes within its scope atomic substituents such as halo, e.g. fluro, chloro and bromo, and also molecular substituents such as nitrile, trifluoro methyl, acyl such as acetyl, nitro, or carbonyl.

Where R¹¹ is an electron withdrawing group, it is suitably acyl such as acetyl, nitrile or nitro.

Preferably, R⁷ and R⁸ are independently selected from fluoro, chloro or alkyl or H. In the case of alkyl, methyl is most preferred.

Preferably, X², X³, Y² and Y³ are all hydrogen.

Alternatively, it is possible that at least one, and possibly all, of X², X³, Y² and Y³ is a substituent other than hydrogen or fluorine, in which instance it is preferred that at least one, and possibly all, of X², X³, Y² and Y³ is an optionally substituted hydrocarbyl group. In such embodiments, it is preferred that at least one, and most preferably all, of X², X³, Y² and Y³ is an optionally substituted alkyl group. Particularly preferred examples are Ci to C₄ alkyl groups, especially methyl or ethyl. Alternatively, at least one, and preferably all, of X², X³, Y² and Y³ are aryl and/or heterocyclic such as pyridyl, pyrimidinyl, or a pyridine or pyrimidine containing group.

In preferred embodiments, R¹ is -R³ -R⁵ = Y¹, X¹ and Y¹ are groups CX²X³ and CY¹Y² respectively and the dotted lines represent an absence of a bond. In these embodiments, the polymerisation may proceed by a cyclopolymerisation reaction.

A preferred group of polymeric precursors are compounds of structure (II)

and in particular compounds of formula (III)

where r is an integer of 1 or more and R⁶ is one or more of a binding group, an optionally substituted hydrocarbyl group, a perhaloalkyi group, a siloxane group, an amide, or a partially polymerised chain containing repeat units.

Where in the compounds of formulae (II) and (III), r is 1 , compounds can be readily polymerised to form a variety of polymer types depending upon the nature of the group R⁶. Embodiments in which r is 1 or 2 are most preferred.

Where in the compounds of formula (II), r is greater than one, polymerisation can result in polymer networks. On polymerisation of these compounds, networks are formed whose properties maybe selected depending upon the precise nature of the R⁶ group, the amount of chain terminator present and the polymerisation conditions employed. Some examples of bridging groups can be found in WO 00/06610.

Preferably, r is 1 , 2, 3 or 4.

Preferably, R⁶ comprises a straight or branched chain hydrocarbyl group, optionally substituted or interposed with functional groups. Advantageously, the straight or branched chain hydrocarbyl is interposed or substituted with one or more of an amine moiety, C(O) or COOH.

In some embodiments, the polymeric precursor is a monomer in which R⁶ is a straight or branched chain hydrocarbyl interposed with an amine moiety, or a pre-polymer obtained by pre-polymerisation of said monomer. Polymeric precursors of this type can be highly advantageous in promoting the adhesion of textile fibres to polymeric materials, and in promoting the adhesion of acid dyes to textile fibres. Preferably, the monomer is a straight or branched chain alkyl group having 1 to 30 carbon atoms, optionally interposed with a cyclic group. In particular in preferred embodiments, the monomer is a compound of formula (IV)

where R¹⁴ is H or C_s H_2s +i , p is 1 to 10, 9 is 0 to 10 and s is 1 to 10.

In other preferred embodiments, the monomer is a compound of formula

(V)

[V] where t and u are independently 1 to 10 and R¹⁴ is H or C_sH_2s+i , where s is 1 to 10.

In other preferred embodiments, the polymeric precursor is a monomer in which R⁶ is a straight or branched chain hydrocarbyl substituted with a COOH end group, or a pre-polymer obtained by pre-polymerisation of said monomer. The monomer may be a straight or branched chain alkyl group having 1 to 30 carbon atoms, optionally interposed with a cyclic group. Advantageously, the monomer is a compound of formula (VI)

where v is 1 to 20.

In alternative embodiments, the polymeric precursor is a monomer in which R⁶ is a straight or branched chain alkyl group having 1 to 30 carbon atoms, or a pre-polymer obtained by pre-polymerisation of said monomer. Polymeric precursors of this type can be advantageous in promoting adhesion between textile fibres and polymeric materials.

In other embodiments still, the polymeric precursor is a monomer in which, R⁶ is a partially or per-halogenated straight or branched chain alkyl group having 1 to 30 carbon atoms, or a pre-polymer obtained by pre-polymerisation of said monomer. Polymeric precursors of this type can be advantageously used to promote adhesion of dyes onto textile fibres. Preferably, the alkyl group is per-halogenated. It is preferred that the alkyl group is fluorinated, most preferably per-fluorinated. In other embodiments still, the polymeric precursor is a monomer in which R¹³ is CO and R⁶ terminates in one or more amine moieties forming a urea structure, or a pre-polymer obtained by pre-polymerisation of said monomer.

In yet further embodiments, the polymeric precursor is a monomer of structure (VII)

where R^6' is a straight or branched chained hydrocarbyl group, optionally substituted or interposed with functional groups, and r is an integer of two or more, or a pre-polymer obtained by a pre-polymerisation of said monomer. Preferably, r is two or three. Polymeric precursors of this type can be advantageously used to promote adhesion of textile fibres to polymeric materials, and to promote adhesion of dyes to textile fibres.

The step of polymerising the polymeric precursor may produce a homopolymer.

Alternatively, the step of polymerising the polymeric precursor may produce a copolymer, the polymeric precursor being mixed with one or more other polymeric precursor. The other polymeric precursor may be according to any of the formulae described herein. Alternatively, the co-monomer may be of a different class of compounds. The monomer may be copolymerised with a cross-linker. In these embodiments, the polymeric precursor may be reacted with a compound of the following formula

where R¹ , R², R⁴, R¹³, and X¹ are as defined in relation to formula (I), r is an integer of 2 or more, and R⁶ is a bridging group of valency r or a bond. Preferably, r is 2. The use of a compound of formula (XI) is particularly advantageous when the polymeric precursor does not include the group -R³ -R⁵- Y¹. However, embodiments of polymeric precursors which include the group - R³ -R⁵==Y¹ may also be reacted with a compound of formula (XII).

The cross-linker may be a compound of formula (XIII)

Other examples of cross-linkers include N, N, N, N- Tetraallylethanediamide and 2,2',2",2"'-(ethane-1 ,2- diylbis(azanetriyl))tetrakis(A/,A/-diallylacetamide).

The monomer or co-monomers may be pre-polymerised to produce a polymeric precursor. Typically, a thermal initiator is used and pre-polymerisation is performed at an elevated temperature above ambient temperature.

The light absorbing substances may be adhered to the polymeric coating by dyeing or through a printing process, such as screen printing. Printing is a preferred way of producing the camouflage pattern.

The light absorbing substances may be adhered to the polymeric coating by applying a formulation to the polymeric coating which may include any desirable further components, such as an anti-foaming agent, thickeners, diluents, etc as is well understood by the skilled reader.

The textile with the camouflage pattern thereon may have a finish applied thereto, such as a fluorocarbon finish or a hydrophilic accelerant to improve wicking.

Whilst the invention has been described above, it extends to any inventive combination or sub-combination of the features set out above or in the following description or claims. For example, elements of the first aspect of the invention may be combined with elements of the second aspect of the invention and wee versa.

Unless otherwise stated, all percentages described below are wt%.

Example 1 Adhesion promotion of acid dyes to m-aramid fabric using an

adhesion promotion layer consisting of a copolymer of N, N-Diallyl- 2 (butyldiallylcarbamoylmethylamino)acetamide and N, N-Diallyl-3- (propylamino)propanamide.

A mixture of N, N-Diallyl-2-(butyl-diallylcarbamoylmethylamino)acetamide (74.4g) and N, N-Diallyl-3-(propylamino)propanamide (18.6g) was pre-heated at 70°C after which thermal initiator (DuPont Vazo67, 5.0g) was added with constant stirring. The reaction mixture was maintained at 70°C for 10 hours with continuous stirring to produce a viscous liquid, after which photoinitiator was added (Ciba Irgacure 819, 2.0g) and dissolved fully into the mixture.

This formulation was then coated onto m-aramid fabric using a reverse roller method to approximately 20 grams per square metre coat weight and cured under a 200W/cm UV lamp using a gallium doped mercury bulb.

Acid dyeing of the treated textile was performed by the application of a water based print paste, which contained the acid dye in solution. The paste was liberally applied to the textile, followed by heating of the dyed textile at 130°C for 60 minutes followed by heating at 180°C for 5 minutes. After cooling the dyed textile was washed in an alkaline solution of potassium carbonate (pH 10), rinsed in water and then dried.

Alternatively, the treated textile was simply treated with an acid dye in aqueous solution, for instance acid green 25 at 5% concentration, and then heated for 10 minutes at 70°C. The sample was then washed in water, then an alkaline solution of potassium carbonate (pH 10) and again rinsed in water before drying.

A camouflage pattern can be produced on a textile using the procedures described in this example.

N, N-Diallyl-2-(butyl-diallylcarbamoylmethylamino) acetamide

N, N-Diallyl-3-(propylamino)propanamide

Synthesis of N, N-Diallyl-2-(butyl-diallylcarbamoylmethylamino) acetamide

Chloroacetyl chloride (>98%, 212g, 1 .883 moles) and dichloromethane (397.5g, 4.680 moles) were added to a reaction vessel and cooled to 5°C. N,N- diallylamine (freshly distilled, 402.57g, 4.143 moles) was added to

ichloromethane (397.5g, 4.680moles) and this mixture was then added dropwise to the chloroacetyl chloride mixture over several hours with constant stirring with the temperature kept below 10°C. The reaction mixture was then left to reach room temperature and then washed in water (1 .51). The organic phase was washed again in water, followed by separation of the organic phase. Solvent and volatiles were then removed from the organic phase under vacuum to yield a yellow oil, which was further purified by column chromatography with ethyl acetate eluent and silica. Eluent was removed under vacuum to yield a yellow oil. Yield -78%.

N,N-Diallyl-2-chloroacetamide (intermediate) (86.75g, 0.500moles), triethylamine (154.38g, 1 .500moles) and tetrahydrofuran (222.25g, 3.082moles) were charged into a reaction flask with 1 -butylamine (99%, 18.29g, 0.250moles) added dropwise over 15 minutes with constant stirring. The temperature of the reaction was brought to reflux and maintained for 4 hours. The reaction was then cooled to room temperature followed by filtration of the triethylamine

hydrochloride salt from the reaction liquor. After removal of solvent under vacuum the product was added to dichloromethane (200ml) and then washed twice in water (300ml). The organic phase was separated, dried with magnesium sulfate and filtered. This was followed by removal of solvent under vacuum to yield a pale yellow oil. Yield ~ 88%.

Synthesis of N, N-Diallyl-3-(propylamino)propanamide

3-bromopropionylchloride in dichloromethane (1 :1 v/v) was added drop wise to a slight molar excess of diallylamine in dichloromethane (DCM) at ~10°C over 2 hours with constant stirring. This was then washed in dilute HCI and dichloromethane and the organic fraction retained. The solution of product in DCM was then purified by column chromatography using silica (60A) and the DCM removed to yield the 3-bromo-N,N-diallylpropylamide intermediate; a yellow liquid. Yield 70%.

The 3-bromo-N,N-diallyipropylamide intermediate (30g, 29mmoles) was added to THF (1 :1 v/v). This was then added dropwise over 2 hours into a stirred, refluxing mixture of 1 -propylamine ( 43.1g, 0.730 mmoles), potassium carbonate (90g, 0.652mmoles) and THF (133.6g, 1 .850mmoles). The reflux was then left to cool over 1 hour with constant stirring.

The cooled reaction mixture was washed in water (400ml), dissolving the potassium carbonate and leaving a clear, yellow organic top layer, which was decanted off. This layer was then washed again in water, separated and dried to yield a yellow liquid N, N-Diallyl-3-(propylamino)propanamide product. Yield ~ 65%. Example 2 Adhesion promotion of acid dyes to m-aramid fabric using an

adhesion promotion layer consisting of benzene-1 ,3,5-tricarboxylic acid-tris-N, N-Diallylamide

Benzene-1 ,3,5-tricarboxylic acid-tris-N, N-Diallylamide was mixed with photoinitiator (ITX, 3% by weight) and amine synergist (4- Dimethylaminobenzoate, 2% by weight) and then applied by reverse roller method to an m-aramid fabric at 20 grams per square metre coating weight. This was cured under a focused 200W/cm UV lamp using an Iron doped mercury bulb.

Synthesis of Benzene-1 ,3,5-tricarboxylic acid-tris-N, N-Diallylamide A mixture of Ν,Ν-Diallylamine (>99%, 128.26g, 1.32 moles) and dichloromethane (106.0g, 1 .248 moles) was added to a funnel and added dropwise over 75 minutes to a reaction vessel containing a cooled mixture (10°C) of 1 ,3,5-trimesoyl chloride (53.1 g, 0.200 moles) in dichloromethane (530. Og, 6.24moles) with constant stirring. The temperature was maintained at < 10°C for the duration of the addition of the diallylamine solution and then left to return to room temperature over another 60 minutes with constant stirring. The organic reaction product was then washed with an excess of water (1x600ml and 2x300ml) to remove the hydrochloride salt of the diallylamine, followed by drying over anhydrous MgS0 . Solids were then filtered off and the solvent removed under vacuum. The crude product was then purified by column chromatography using a silica column and dichloromethane as eluent. The dichloromethane was again removed under vacuum to yield a pale yellow, viscous product. Yield 60.2%.

Basic dyes may be applied in a similar way and may show enhanced dyeing when an acid group is present as part monomer structure.

Example 3 Adhesion promotion of basic dyes to m-aramid fabric using an adhesion promotion layer consisting of 4-(Diallylamino)-4- oxobutanoic acid and N, N, N', N'-tetraallylethanediamide

A mixture of 4-(Diallylamino)-4-oxobutanoic acid and N, N, Ν', N'- Tetraallylethanediamide was prepared in the ratio 3:1 by weight respectively. To this photoinitiator was added (Ciba Irgacure 819, 3% by weight to total monomer) and stirred until fully dissolved. This formulation was then coated onto m-aramid fabric using a reverse roller method to approximately 20 grams per square metre coat weight and cured under a focused 120W/cm UV source using a gallium doped mercury bulb.

The treated fabric was then dyed by immersion of the fabric in a solution of basic blue 26 (3wt% solution) in water at 70°C for 10 minutes. This was followed by washing of the fabric in a dilute acetic acid solution, rinsing in thoroughly in water and drying with warm air. A camouflage pattern can be produced on a textile using the procedures described in this example.

4-(Diallylamino)-4-oxobutanoic acid

Synthesis of 4-(Diallylamino)-4-oxobutanoic acid

A solution of diallylamine (>99%, 24.5g) in dichloromethane (50ml) was added drop-wise over 1 hour to a solution of succinic anhydride (>98%, 25.3g) in dichloromethane (200ml) with constant stirring. The temperature throughout the addition of the diallylamine was maintained between 10- 20°C and with constant stirring throughout the reaction. After all the diallylamine was added the reaction was allowed to proceed for 30 minutes, after which the mixture was washed once with HCI (100ml, 3 molar), once with saturated potassium carbonate solution (200ml) and then twice in water (200ml). The organic phase was dried over MgS0₄, filtered and the solvent then removed in vacuum to yield a pale yellow oil.

N, N, N, N-Tetraallylethanediamide

Synthesis of N, N, N, N-Tetraallylethanediamide

Fresh, dry oxaloyl chloride (CIOOCCOOCI) (200 mmoles) was placed into a 3-necked round bottomed (RB) flask with 200 ml of dry dichloromethane. Freshly distilled diallylamine (400mmoles) was added to triethylamine (400mmoles), further diluted (1 :1 v/v) in dry dichloromethane then added into a dropping funnel and placed onto the reaction flask. Nitrogen gas was pumped through the vessel through the other two necks. To neutralise HCI produced, the waste gas was bubbled through a CaC0₃ solution. The reaction vessel was then placed into a salt water/ice bath and once the contents were cooled the diallylamine/triethylamine/DCM was added dropwise to the acid chloride solution with continual magnetic stirring of the mixture. The temperature was monitored and maintained between 5-10°C. The dropping of the diallylamine and triethylamine was stopped after three hours and the reaction was left to stir for another hour. Thin layer chromatography using ethyl acetate and an alumina was used to monitor the reaction comparing starting material to the product. Iodine was used to develop the plate and the reaction product could be seen as a spot that had been eluted much further than the starting material.

To remove the amine chloride and excess diallylamine the reaction liquor was washed in 3M HCI. The monomer stayed in the DCM fraction and was removed using a separating funnel. Two washes of 100ml HCI were used. The solvent was then removed in a rotary evaporator.

The product was added to dichloromethane (1 :1 v/v) and passed through a silica gel (Merck, grade 60 for chromatography) column with dichloromethane as the eluent.

Example 4 Adhesion promotion of an acid dye to nylon 6,6 fabric using an adhesion promotion layer consisting of a copolymer of N, N-Diallyl- 2 (butyldiallylcarbamoylmethylamino)acetamide and N, N-Diallyl-3- (propylamino)propanamide.

A mixture of N, N-Diallyl-2-(butyl-diallylcarbamoylmethylamino)acetamide (56. Og) and N, N-Diallyl-3-(propylamino)propanamide (14.0g) was pre-heated to 75°C. To this mixture a solution of thermal initiator (DuPont Vazo 67, 3.0g) in N, N-Diallyl-2-(butyl-diallylcarbamoylmethylamino) acetamide (21.6g) and N,N- Diallyl-3-(propylamino)propanamide (5.4g) was added over 10 hours with temperature maintained at 75°C with constant stirring and under a nitrogen atmosphere. After the 10 hours reaction time the solution was left to cool and the photoinitiator 2-isopropyl thioxanthone (ITX) (2.0g) and synergist ethyl 4- (dimethylamino) benzoate (EDB) (3.0g) were added. Both additives

were fully dissolved and mixed into the monomer mixture prior to use.

This formulation was then coated onto nylon 6,6 fabric using a reverse roller method to approximately 20 grams per square metre coat weight and cured under a 200W/cm UV lamp using a gallium doped mercury bulb.

Acid dyeing of the treated textile was performed by the application of a water based print paste, which contained the acid dye in solution. The paste was liberally applied to the textile, followed by heating of the dyed textile at 130°C for 60 minutes followed by heating at 180°C for 5 minutes. After cooling the dyed textile was washed in an alkaline solution of potassium carbonate (pH 10), rinsed in water and then dried. A camouflage pattern can be produced on a textile using the procedures described in this example.

Example 5 Adhesion promotion of an acid dye to m-aramid fabric using an adhesion promotion layer consisting of a polymer made with N, N- Diallyl-2(-butyl-diallylcarbamoylmethylamino)acetamide

N, N-Diallyl-2-(butyl-diallylcarbamoylmethylamino)acetamide (70. Og) was pre-heated to 75°C after which a mixture of thermal initiator (DuPont Vazo 67, 3.0g) in N, N-Diallyl-2-(butyl-diallylcarbamoylmethylamino)acetamide (27. Og) was added over 10 hours with the temperature maintained at 75°C with constant stirring and under a nitrogen atmosphere. After the 10 hours reaction time the solution was left to cool and the photoinitator 2-isopropyl thioxanthone (ITX) (2.0g) and synergist ethyl 4-(dimethylamino) benzoate (EDB) (3.0g) were added. Both additives were fully dissolved and mixed into the monomer mixture prior to use.

This formulation was then coated onto m-aramid fabric using a reverse roller method to approximately 10 grams per square metre coat weight and cured under a 200W/cm UV lamp using an iron doped mercury bulb.

Acid dyeing of the treated textile was performed by the application of a water based print paste, which contained the acid dye in solution. The paste was liberally applied to the textile, followed by heating of the dyed textile at 130°C for 60 minutes followed by heating at 180°C for 5 minutes. After cooling the dyed textile was washed in an alkaline solution of potassium carbonate (pH 10), rinsed in water and then dried. A camouflage pattern can be produced on a textile using the procedures described in this example. Example 6 Camouflage printing of an m-aramid fabric with an acid dye and a pigment

1. Coating of N, N-Diallyl-2-(butyl-diallylcarbamoylmethylamino) acetamide onto m-aramid

Nomex III® aramid (145gsm) used was coated with a prepolymerised N, N- Diallyl-2-(butyl-diaIlylcarbamoylmethylamino) acetamide formulation in the following manner. N, N-Diallyl-2-(butyl-diallylcarbamoylmethylamino)acetamide (70. Og) was pre-heated to 75°C after which a mixture of thermal initiator (DuPont Vazo 67, 3.0g) in N, N-Diallyl-2-(butyl-diallylcarbamoylmethylamino)acetamide (27. Og) was added over 10 hours with the temperature maintained at 75°C with constant stirring and under a nitrogen atmosphere. After the 10 hours reaction time the solution was left to cool and the photoinitator 2-isopropyl thioxanthone (ITX)

(2.0g) and synergist ethyl 4-(dimethylamino) benzoate (EDB) (3.0g) were added. Both additives were fully dissolved and mixed into the monomer mixture prior to use.

This formulation was then coated onto m-aramid fabric using a reverse roller method to approximately 10 grams per square metre coat weight and cured under a 240W/cm UV lamp using an iron doped mercury bulb.

2. Printing of camouflage colours on Nomex III® aramid

The treated aramid textile was then sequentially printed with three

camouflage colours using a rotary screen process. The printed textile was then dried by hot air so it was dry to touch, followed by steaming over 10 minutes at 102°C (production scale) to cross-link the binder and fix the dyes. Washing of the excess dye was then performed by an initial cold rinse followed by washing in hot water (90°C), with an additional cold rinse followed by drying of the textile.

The coloration of each print paste colour was mostly achieved by varying amounts of acid dyes present with a carbon based pigment also used to produce an appropriate Infra red reflectance. The brown coloured print paste contained a mixture of Magnaprint™ SFR binder (50g), Urea (50g), Lyoprint™ AP antifoam agent (4g), ammonium sulphate (1 Og), water diluent (21 Og), Prisulon™ DCA1200S thickener (13% aqueous, 1400g), two or more premetallised acid dyes, a brown pigment and also a carbon based pigment to provide the necessary Infra red reflectance.

The light sand coloured print paste contained a mixture of Magnaprint™ SFR binder (200g), Urea (50g), Lyoprint™ AP antifoam agent (4g), ammonium sulphate (10g), water diluent (125g), Prisulon™ DCA1200S thickener (13% aqueous, 1540g), two or more premetallised acid dyes, a brown pigment and also a carbon based pigment to provide the necessary Infra red reflectance.

The sand coloured print paste contained a mixture of Magnaprint™ SFR binder (200g), Urea (50g), Lyoprint™ AP antifoam agent (4g), ammonium sulphate (10g), water diluent (260g), Prisulon™ DCA1200S thickener (13% aqueous, 1400g), two or more premetallised acid dyes, a brown pigment and also a carbon based pigment to provide the necessary Infra red reflectance.

A number of physical properties were tested to show the effectiveness of the camouflaged textile. Good performance was seen for key properties such as laundering, lightfastness and flame resistance:

Physical Properties Result Test Method

Flame Resistance No flame / hole BS EN ISO 15025

After Flame 0.0 X 0.0 2.0 MAX After Glow 0.0 X 0.0 2.0 MAX Colourfastness:

Water 4.5 BS EN ISO 105-E01

Laundering C2S @ 60° 4 .5 BS EN ISO 105C06 Wet / Dry Rubbing

3/4 BS EN ISO 105-X12

Perspiration acid/alkali 4.5 / 4.5 BS EN ISO 105-E04

Colour Abrasion <35000 rubs BS EN ISO 12947-2

Pilling 4.5 BS EN ISO 12945-1

Light Fastness 5+ BS EN ISO 105B02

Dimensional Stability 2.0x2.0 BS EN ISO 25077

Tear Strength 35x25 BS EN ISO 13937-3

Breaking Strength 750x650N BS EN ISO 13934-1 Other advantages associated with the invention include improved wearer comfort resulting from the ability to coat lightweight fabrics such as aramids, and excellent infra-red spectral compliance, even across extended wavelength ranges. Enhancements have been observed in textile durability, and there are cost and flexibility benefits associated with the production process of the present invention.

Textiles of the invention can be in the form of uniforms or other item of clothing, or can be supplied as a cloth as a precursor to the manufacture of garments. Textiles of the invention can be used to produce other articles, such as tents, nets, covers or screens.

Claims

1 . A textile having a camouflage pattern thereon including:

a textile piece having a polymeric coating; and

independently selected from hydrogen, halo or hydrocarbyl, and either one of R⁹ or R ⁰ is hydrogen and the other is an electron withdrawing group, or R⁹ and R¹⁰ together form an electron withdrawing group; and

R⁴ and R⁵ are independently selected from CH or CR¹¹ where R¹¹ is an electron withdrawing group, the dotted lines indicate the presence or absence of a bond, X¹ is a group CX²X³ where the dotted line bond to which it is attached is absent and a group CX² where the dotted line bond to which it is attached is present, Y¹ is a group CY²Y³ where the dotted line bond to which it is attached is absent and a group CY² where the dotted line bond to which it is attached is present, and X², X³, Y² and Y³ are independently selected from hydrogen, fluorine or other substituents, R¹ is selected from hydrogen, halo, nitro, hydrocarbyl, optionally substituted or interposed with functional groups, or ·· · · ; and

R ³ is C(0) or S(0)₂.

2. A textile according to Claim 1 in which at least one light absorbing substance absorbs visible light, and is adhered to the polymeric coating to provide a visible camouflage pattern.

3. A textile according to Claim 1 or Claim 2 in which at least one light absorbing substance absorbs infra-red radiation, and is adhered to the polymeric coating to provide an infra-red camouflage pattern.

4. A textile according to any one of Claims 1 to 3 in which the light absorbing substances are selected so as to provide as part of the camouflage pattern at least one colour selected from beige, brown, black and khaki.

5. A textile according to any previous Claim in which at least one light absorbing substance is a dye, and wherein the polymeric coating acts to promote adhesion of the dye to the textile piece.

6. A textile according to Claim 5 in which the dye is an acid dye.

7. A textile according to any previous Claim in which at least one light absorbing substance is a pigment contained in a binder, in which the polymeric coating acts to promote adhesion to the binder and/or pigment to the textile piece.

8. A textile according to Claim 7 in which the pigment is carbon black.

9. A textile according to any previous Claim in which the textile piece beneath the polymeric coating is pre-coloured with one or more pre-colouring light absorbing substances.

10. A textile according to any previous Claim containing aramid fibres.

1 1. A textile according to Claim 10 in which the textile is formed entirely from aramid fibres, or is formed from a mixture of aramid fibres and fibres of at least one other kind.

12. A method of producing a textile having a camouflage pattern thereon including the steps of:

providing a polymeric precursor which includes a group of sub-formula (I)

R²— R⁴.^ «

— R¹³-N R¹ _[∑] where R² and R³ are independently selected from (CR⁷R⁸)_n, or a group CR⁹R¹⁰, CR⁷R⁸CR⁹R¹⁰ or CR⁹R¹⁰CR⁷R⁸ where n is 0, 1 or 2, R⁷ and R⁸ are

independently selected from hydrogen, halo or hydrocarbyl, and either one of R⁹ or R ⁰ is hydrogen and the other is an electron withdrawing group, or R⁹ and R¹⁰ together form an electron withdrawing group, and

R⁴ and R⁵ are independently selected from CH or CR¹¹ where R¹¹ is an electron withdrawing group, the dotted lines indicate the presence or absence of a bond, X¹ is a group CX²X³ where the dotted line bond to which it is attached is absent and a group CX² where the dotted line bond to which it is attached is present, Y¹ is a group CY Y³ where the dotted line bond to which it is attached is absent and a group CY² where the dotted line bond to which it is attached is present, and X², X³, Y² and Y³ are independently selected from hydrogen, fluorine or other substituents,

R¹ is selected from hydrogen, halo, nitro, hydrocarbyl, optionally substituted or interposed with functional groups, or R³— R⁵ =Y , and

R¹³ is C(0) or S(0)₂; providing a textile piece;

coating the textile piece with the polymeric precursor;

13. A method according to Claim 12 in which the polymeric precursor is a compound of structure (II)

where r is an integer of 1 or more and R⁶ is one or more of a bridging group, an optionally substituted hydrocarbyl group, a perhaloalkyl group, a siloxane group, an amide, or a partially polymerised chain containing repeat units.

14. A method according to Claim 13 in which the polymeric precursor is a compound of structure [III]

15. A method according to Claim 13 or Claim 14 in which R⁶ comprises a straight or branched chain hydrocarbyl group, optionally substituted or interposed with functional groups.

16. A method according to Claim 15 in which the straight or branched chain is interposed or substituted with one or more of an amine moiety, C(O) or COOH.

17. A method according to Claim 16 in which the polymeric precursor is a monomer in which R⁶ is a straight or branched chain hydrocarbyl interposed with an amine moiety, or a pre-polymer obtained by pre-polymerisation of said monomer.

18. A method according to Claim 17 in which the monomer is a straight or branched chain alkyl group having 1 to 30 carbon atoms, optionally interposed with a cyclic group.

19. A method according to Claim 18 in which the monomer is a compound of Formula (IV)

where R is H or C_sH_2s +i , p is 1 to 10, q is 0 to 10 and s is 1 to 10.

20. A method according to Claim 18 in which the monomer is a compound of

Formula (V)

21. A method according to Claim 16 in which the polymeric precursor is a monomer in which R⁶ is a straight or branched chain hydrocarbyl substituted with a COOH end group, or a pre-polymer obtained by pre-polymerisation of said monomer.

22. A method according to Claim 21 in which the monomer is a straight or branched chain alkyl group having 1 to 30 carbon atoms, optionally interposed with a cyclic group.

23. A method according to Claim 22 in which the monomer is a compound of formula (VI)

where v is 1 to 20.

24. A method according to Claim 15 in which the polymeric precursor is a monomer in which R⁶ is a straight or branched chain alkyl group having 1 to 30 carbon atoms, or a pre-polymer obtained by pre-polymerisation by said monomer.

25. A method according to Claim 15 in which the polymeric precursor is a monomer in which R⁶ is a partially or per-halogenated straight or branched chain alkyl group having 1 to 30 carbon atoms, or a pre-polymer by pre-polymerisation of said monomer.

26. A method according to Claim 17 in which the polymeric precursor is a monomer in which R¹³ is CO and R⁶ terminates in one or more amine moieties thereby forming a urea structure, or a pre-polymer obtained by pre- polymerisation of said monomer.

27. A method according to Claim 13 in which the polymeric precursor is a monomer of structure (VII)

r

where R^{6 '} is a straight or branched chain hydrocarbyl group, optionally substituted or interposed with functional groups, and r is an integer of 2 or more, or a pre-polymer obtained by pre-polymerisation of said monomer.