Rylene-based UV-curable security ink composition

Abstract

The present invention relates to the field of UV-curable security ink compositions comprising a rylene-based compound, a radically curable monomer, oligomer, or mixture thereof, and a radical photoinitiator. The present invention further relates to security features obtained by applying or printing the security ink compositions, articles or documents comprising said security features, and methods for making security features comprising the UV-curable security ink compositions.

Description

Detailed Description of the Invention

[0001] [Field of the Invention]

[0001] The present invention relates to the field of UV-curable security ink compositions based on rylene-based compounds and their use in security printing inks and security features based on such security inks.

[0002] [Background of the invention]

[0002] With the ever-improving quality of color copying and printing technology, in an attempt to protect security documents such as banknotes, value documents or cards, transport tickets or cards, tax banderols, and product labels, it has become conventional practice to incorporate various security features into these documents that resist duplication and protect against counterfeiting, tampering, or unauthorized duplication.

[0003]

[0003] As the threat of counterfeiting secure documents such as currency, passports, or identity cards grows worldwide, this situation has become a very serious problem for governments and society at large. For example, criminal organizations may use fake passports or identity cards for human trafficking. As copying technology becomes increasingly sophisticated, it becomes increasingly difficult to clearly distinguish fake documents from originals. Therefore, document security has a significant impact on countries' economies and on victims of illicit trade involving counterfeit documents.

[0004]

[0004] Security features are also incorporated into (goods) tax stamps. The primary purpose of these stamps is to provide governments with a physical means of collecting tax. Other purposes may be to provide a tamper-proof / reuse-proof seal, or as a carrier of a serialization code for item-level production monitoring and supply chain tracking and tracing.

[0005]

[0005] Accordingly, security features are incorporated into documents to ensure the integrity of the document. Security features can generally be classified as "covert" security features, on the one hand, and "overt" security features, on the other hand. The protection offered by covert security features relies on the concept that such features are difficult to detect, typically requiring specialized equipment and knowledge for detection, whereas "overt" security features, while still difficult to manufacture and / or copy, rely on the concept that they are easily detectable by unaided human senses; for example, such features may be detectable by sight and / or touch. However, the effectiveness of an overt security feature depends heavily on its ease of recognition as a security feature, since most users, especially those without prior knowledge of the security feature of a secured document or item, will actually conduct a security check based on said security feature only if they have actual knowledge of its existence and nature.

[0006] UV-curable ink compositions are known in the art and are widely used to impart security features. They cure by rapid, light-induced polymerization. The UV-curing process is essentially solvent-free, greatly reducing the need for time-consuming and expensive contamination abatement procedures.

[0007] UV-curable ink compositions offer several other benefits not associated with thermally cured coatings. First, they offer substantial economic benefits due to faster cure times. Furthermore, heat-sensitive materials can be safely coated and cured with UV light without thermal degradation of the heat-sensitive substrate. In addition, UV light is widely available, resulting in relatively low energy costs.

[0008]

[0008] A variety of pigments and dyes can be added to UV-curable ink compositions to impart specific colors, and such pigments and dyes are based on a vast variety of chemical structures.

[0009] Fluorescent rylene-based dyes or pigments are known in the art for high performance covert security features (e.g., U.S. Patent Application Publication No. 20080167467). These compounds are primarily based on rylene moieties, as illustrated below. Examples of rylene-type dyes or pigments are perylene, terrylene, and quaterrylene.

[0010]

[0010] It is known that polymer-grafted rylene compounds can be incorporated into security ink compositions. For example, International Publication No. 2011 / 147857 A1 discloses perylene-based printing ink compositions, and International Publication No. 2012 / 160182 A1 discloses terylene- and quaterrylene-based ink compositions. The solubility of prior art rylene dyes is improved by covalently grafting polymeric phenol groups to the rylene moiety. However, rylene dyes still suffer from various problems, such as poor fluorescence, lightfastness, and poor solubility in ink compositions. In particular, polymer-grafted rylene compounds may be required in amounts of up to 15% by weight in pigmented ink compositions to ensure good detectability. This high amount, combined with incompatibility with the monomers and / or oligomers used in UV-curable ink compositions, can lead to poor printing performance.

[0011]

[0011] Apart from the above, there is a constant need to ensure good and uniform printability of security ink compositions and to ensure easy and reliable detection of security features using existing equipment while avoiding (visible) print defects. An additional economic benefit is to ensure the addition of a minimum amount of (rylene-based) dyes or pigments to the ink composition in order to ensure uniformity and better printability of the ink composition.

[0012]

[0012] Therefore, there remains a need for UV curable ink compositions that overcome the deficiencies of the prior art.

[0013] [Summary of the Invention] In one aspect, the present invention provides a method for producing a medicament for the treatment of a pulmonary arthritis, comprising: a) about 40 to about 95% by weight, preferably about 60 to 95% by weight, of one or more radically curable monomers, one or more oligomers, or a mixture thereof; b) about 0.1 to about 20% by weight, preferably about 1 to 15% by weight, of at least one free radical photoinitiator; c) about 0.005 to about 5% by weight, preferably about 0.01 to 1% by weight, of at least one compound P, (1) and (2) [ka] (In the formula, (W) is preferably a rylene moiety (W) comprising any one of a perylene, terrylene, or quaterrylene core structure, and at least one aryl group of formula (3) bonded to the rylene moiety (W): [ka] a rylene moiety containing a substituent of R 1 , R 2 , R 3 are independently carbocyclic or heterocyclic substituents, and R 1 and R 2 is preferably directly attached to the imide N of the rylene moiety (W), and in the case of compound (2), R 3 is directly attached to the naphthalene ring, ----- is R 3 indicates the optional presence of substituents, Ar 4 is an aromatic substituent, Y is a linker, R' is either H or methyl a compound P having a structure selected from the group consisting of: d) optionally, about 0.1 to about 2 wt. % of at least one photosensitizer; e) optionally, from about 0.1 to about 20% by weight of at least one colorant; f) optionally, from about 0.01 to about 10% by weight of at least one additive, preferably from about 0.01 to about 1% by weight of at least one surfactant; wherein the weight percent is based on the total weight of the UV-curable security ink composition.

[0014] In another aspect, the present invention relates to security features made with a cured layer of the UV-curable security ink composition described herein.

[0015] In another aspect, the present invention relates to a security document or article including a security feature as described herein.

[0016] In yet another aspect, the present invention provides a method of making a security feature described herein, comprising: a) applying a UV curable security ink composition described herein to a substrate, preferably by a printing process; b) at least partially curing the UV-curable security ink composition from step a), wherein the curing is preferably performed using a UV-LED light source, more preferably a UV-LED light source having a wavelength of about 360 nm to about 410 nm; The present invention relates to a method, including: [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 shows a security feature in the form of a QR code obtained by printing a UV curable security ink composition described herein.

[0018] [Detailed explanation] definition The following definitions shall be used to interpret the meaning of terms discussed in this specification and recited in the claims.

[0019]

[0019] As used herein, the article "a" refers to one as well as more than one and does not necessarily limit the noun to which it refers to singular.

[0020]

[0020] As used herein, the term "about" means that the amount or value in question may be the specified value or another value of comparable order. This expression is intended to convey that similar values ​​within ±5% of the indicated value will promote the same results or effects according to the present invention.

[0021]

[0021] As used herein, the term "UV" (ultraviolet) is intended to mean radiation having wavelength components in the UV portion of the electromagnetic spectrum, typically between 200 nm and 420 nm.

[0022]

[0022] As used herein, the term "at least one" is meant to define one or more than one, for example, one or two or three.

[0023] As used herein, the term "and / or" means that either all or only one of the elements of the group may be present. For example, "A and / or B" shall mean "A only, or B only, or both A and B." In the case of "A only," the term also encompasses the possibility that B is absent, i.e., "A only and no B."

[0024]

[0024] As used herein, the term "comprising" is intended to be non-exclusive and open-ended. Thus, for example, a coating composition containing compound A may contain compounds other than A. However, the term "comprising" also encompasses the more restrictive meanings of "consisting essentially of" and "consisting of," as specific embodiments thereof. For example, "a fountain solution comprising A, B, and optionally C" may consist (essentially) of A and B, or may consist (essentially) of A, B, and C.

[0025] The term "security document" refers to a document that is typically protected against counterfeiting or fraud by at least one security feature. Examples of security documents include, but are not limited to, value documents and value items.

[0026]

[0026] The term "security feature" is used to denote an image, pattern, or graphic element that can be used for authentication purposes.

[0027]

[0027] When "preferred" embodiments / features are referred to in this specification, combinations of these "preferred" embodiments / features shall also be considered to be disclosed, so long as such combinations of "preferred" embodiments / features are technically meaningful.

[0028] The term "rylene moiety" is used to refer to the general structure shown below: As used herein, the term "rylene moiety" includes rylene-based compounds such as perylene, terrylene, and quaterrylene moieties, or even pentalylene and hexarylene derivatives. For clarity, a rylene moiety refers to a rylene core (e.g., perylene) having two diimide moieties, as illustratively shown below: [ka]

[0029] The term "Ar" is used to indicate an aromatic substituent.

[0030]

[0030] The term "wt %" refers to the amount of a reference component based on the total weight of the UV curable security ink composition.

[0031] The present invention provides a UV-curable security ink composition comprising at least one compound P as described herein.

[0032] P is (1) and (2) [ka] A compound having a structure selected from the group consisting of:

[0033] In one embodiment, as described herein, (W) preferably comprises any one of a perylene, terrylene, or quaterrylene core structure and has at least one of formula (3): [ka] is a rylene moiety containing a substituent of

[0034] In a preferred embodiment, the rylene moiety (W) may be selected from the group consisting of a perylene, terrylene, or quaterrylene core structure, the core structure having two diimide moieties.

[0035] At least one substituent (3) is attached to the rylene moiety. Preferably, the substituent (3) is attached to the perylene, terrylene, or quaterrylene core structure at its corresponding naphthalene ring(s). It will be apparent to those skilled in the art that the placement of the at least one substituent (3) on the naphthalene ring of the rylene moiety (W) can occur only at chemically feasible positions. The rylene moiety (W) may have multiple substituents (3) on different naphthalene rings of the rylene moiety (W); i.e., rylene moieties having two (diacrylate) or more (multiacrylate) substituents (3) are contemplated. Therefore, isomeric rylene moieties (W) bearing substituents (3) are also possible. Consequently, even mixtures of isomerically substituted rylene moieties (W) are possible. In a preferred embodiment, at least two substituents (3) (i.e., diacrylate) are present on the rylene moiety (W).

[0036] At least one of the substituents (3) has the structure shown above. 4 The substituents can be any aromatic group. Preferably, Ar 4 The group is a phenyl ring. The phenyl ring may be substituted or unsubstituted. If substituted, the phenyl ring may further contain a C1-C6 alkyl group and isomers thereof as a substituent.

[0037] At least one of the substituents (3) further comprises a linker Y. The linker Y is -(CH2) j -, -O-(CH2) k -, -[-(CH2) l -O] m -(CH2) p and j=0 to 6, k=1 to 6, l=1 to 3, m=1 to 3, and p=1 to 3. Preferably, the linker Y is selected from the group consisting of at least one -(CH2) j - group, j=1 to 6, and as illustrated in formula (3), 4 The moiety is linked to the O atom.

[0038]

[0038] At least one substituent (3) further comprises at least one (meth)acrylate moiety. In a preferred embodiment, at least one substituent (3) comprises one (meth)acrylate moiety. The R' group can be either hydrogen or methyl.

[0039] In another embodiment, at least one compound P can have structure (2), as described herein. As shown structurally, compound P having formula (2) lacks an imide moiety compared to rylene moiety (W). In place of the missing imide moiety, compound (2) contains a different substituent R 3 In the illustrated structure (2), this is indicated by the bond pattern ----. Thus, R 3 The substituents are optional.

[0040] At least one compound P having structure (2) also includes at least one substituent (3) as described herein. It should be noted that the position of the at least one substituent (3) shown in formula (2) is merely exemplary. Thus, it does not preclude at least one substituent (3) being attached to another naphthalene ring of the core structure of formula (2). As previously described for the rylene moiety (W), even more than one substituent (3) may be present. In one particular embodiment, at least one substituent (3) as described herein is selected from the group consisting of R 3 In such cases, R 3 There are no substituents, i.e., at least one substituent (3) is R 3 It replaces the substituent.

[0041] At least one compound P is R 1 , R 2 , and R 3 R is a cyclic or heterocyclic group, 1 , R 2 , or R 3 R 1 and R2 In the case of R, the substituent is preferably directly attached to the imide N of the rylene moiety (W), 3 In this case, the substituent is optional and may be directly attached to the naphthalene ring, as shown in formula (2).

[0042]

[0042] Carbocyclic substituent R 1 , R 2 , or R 3 may be selected from the group consisting of alicyclic and aromatic substituents, optionally bearing further substituents. Preferably, the substituent R 1 , R 2 , or R 3 is aromatic in nature and optionally substituted. Thus, in a preferred embodiment, R 1 Ar 1 is a substituent, R 2 Ar 2 is a substituent, R 3 Ar 3 In another preferred embodiment, R 1 , R 2 , or R 3 is either directly attached to the imide N or attached to a methylene chain ((-CH2) z ), and even more preferably an alicyclic or aromatic substituent, wherein z is 1 to 6, and the methylene chain is the point of attachment to the rylene moiety (W) or the imide N of the naphthalene ring of compound (2), as described above. 1 , R 2 , or R 3 The substituents may independently be heterocyclic substituents, preferably N-containing heterocyclic substituents. For clarity, the R bonded directly to the diimide N may be a heterocyclic group. 1 and R 2 It will be apparent to one skilled in the art that may not be a heterocyclic, particularly an N-containing heterocyclic, substituent.

[0043] In a preferred embodiment, the Ar 1~3 The substituent may have the structure (4) depicted below, where R4 , R 5 , and R 6 are independently hydrogen, halogen, C1-C4 alkyl and its isomers, C1-C4 alkoxy, C1-C4 aminoalkyl, or a (fused) aromatic group. The term "fused aromatic" encompasses the types of fused aromatic-alicyclic substituents and fused bicyclic or tricyclic compounds of compound (4). [ka]

[0044]

[0044] R 1 , R 2 , or R 3 Some specific examples of substituents are represented by the formulae below, wherein: * - represents the point of contact of the rylene moiety (W) to the imide N or the imide N of formula (2), or the point of direct contact with the naphthalene moiety of formula (2) (i.e., R 3 ), and X represents F, Br, Cl, OCH3, or OPh. Even if the substituent X is shown in only some of the formulas in the table below, those skilled in the art can assume that said substituent is also present in other formulas described herein, as long as it is chemically possible. It should be noted that the formulas listed below do not include an exhaustive list, but that those skilled in the art can consider other chemically equivalent substituents. [Table 1] JPEG2025538976000009.jpg193149

[0045]

[0045] The UV-curable security ink composition described herein comprises a UV radically curable compound. In a preferred embodiment, the UV-curable security printing ink composition comprises one or more radically curable monomers, or one or more radically curable oligomers, or a mixture thereof. Alternatively, the UV-curable security printing ink composition described herein may further comprise one or more cationically curable compounds in addition to the radically curable compounds described herein.

[0046]

[0046] The UV radical curable composition comprises one or more radical curable compounds that cure by a free radical mechanism, which consists of the energy activation of at least one free radical photoinitiator, which liberates free radicals that then initiate polymerization to form the binder. Preferably, the radical curable compound is selected from (meth)acrylates, preferably from the group consisting of epoxy (meth)acrylates, (meth)acrylated oils, polyester and polyether (meth)acrylates, aliphatic or aromatic urethane (meth)acrylates, silicone (meth)acrylates, acrylic (meth)acrylates, and mixtures thereof. In the context of the present invention, the term "(meth)acrylate" refers to acrylates and the corresponding methacrylates.

[0047] In embodiments where the UV-curable security ink composition is a screen printing ink composition, a flexographic printing ink composition, or a rotogravure printing ink composition, the composition preferably comprises one or more radically curable oligomers in an amount of preferably from about 25% to about 55% by weight, one or more radically curable monomers selected from the group consisting of tri(meth)acrylates, tetra(meth)acrylates, and mixtures thereof, preferably in an amount of from about 10% to about 50% by weight, and optionally one or more radically curable monomers selected from the group consisting of mono(meth)acrylates, di(meth)acrylates, and mixtures thereof, preferably in an amount of from about 0% to about 50% by weight, more preferably from about 0% to about 40% by weight, and even more preferably from about 0% to about 30% by weight.

[0048]

[0048] In embodiments where the UV-curable security ink composition is an ink composition for non-contact fluid microdispensing process printing, preferably an ink composition for inkjet printing, more preferably an ink composition for drop-on-demand (DOD) inkjet printing, the composition preferably comprises one or more radically curable monomers selected from the group consisting of mono(meth)acrylates, di(meth)acrylates, tri(meth)acrylates, tetra(meth)acrylates, and mixtures thereof, preferably in an amount of from about 40% to about 95% by weight, more preferably from about 60% to about 95% by weight, and may further comprise one or more radically curable oligomers, preferably in an amount of from about 0% to about 35% by weight, more preferably from about 0% to about 20% by weight, the weight percentages being based on the total weight of the UV-curable security ink composition.

[0049]

[0049] As used herein, a radically curable oligomer refers to a relatively high molecular weight oligomeric compound having a weight average molecular weight (MW) of ≥ 400 g / mol, preferably ≥ 800 g / mol, and more preferably ≥ 1000 g / mol. The radically curable oligomer described herein is preferably a (meth)acrylate oligomer that may be branched or essentially linear, and the one or more (meth)acrylate functional groups may each be a terminal group and / or a pendant side group attached to the oligomer backbone. Preferably, the radically curable oligomer is a (meth)acrylic oligomer, a urethane (meth)acrylate oligomer, a polyester (meth)acrylate oligomer, a polyether-based (meth)acrylate oligomer, an epoxy (meth)acrylate oligomer, and mixtures thereof.

[0050]

[0050] The one or more mono(meth)acrylate monomers described herein are preferably selected from the group consisting of alkyl(meth)acrylates, cycloalkyl(meth)acrylates, benzyl(meth)acrylate, phenyl(meth)acrylate (including phenoxyalkyl(meth)acrylates, e.g., phenoxyethyl acrylate), cyclic trimethylolpropane formal acrylate, tetrahydrofurfuryl acrylate, aliphatic urethane(meth)acrylates, alkoxylated (especially ethoxylated or propoxylated) compounds thereof, and mixtures thereof.

[0051] Suitable di(meth)acrylate monomers include, but are not limited to, ethylene glycol diacrylate, ethylene glycol dimethacrylate; 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate; 1,3-butanediol diacrylate, 1,3-butanediol dimethacrylate; 2-methyl-1,3-propanediol diacrylate, 3-methyl-1,5-pentanediol diacrylate; 2-butyl- 2-Ethyl-1,3-propanediol diacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate; neopentyl glycol diacrylate, neopentyl glycol dimethacrylate; 1,9-nonanediol diacrylate; 1,9-nonanediol dimethacrylate; 1,10-decanediol diacrylate, 1,10-decanediol dimethacrylate, alkoxylated (especially ethoxylated and propoxylated) 1, 6-hexanediol diacrylate; propoxylated neopentyl glycol diacrylate; ethoxylated 2-methyl-1,3-propanediol diacrylate; tricyclodecane dimethanol diacrylate; diethylene glycol diacrylate, diethylene glycol dimethacrylate; dipropylene glycol diacrylate; triethylene glycol diacrylate, triethylene glycol dimethacrylate; tripropylene glycol diacrylate; tripropylene glycol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate; polyethylene glycol 200 / 400 / 600 diacrylate, polyethylene glycol 200 / 400 / 600 dimethacrylate; ethoxylated (EO2 / EO3 / EO4 / EO10) bisphenol A diacrylate, and ethoxylated (EO2 / EO3 / EO4 / EO10) bisphenol A dimethacrylate.

[0052] The one or more tri(meth)acrylate monomers described herein are preferably trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, alkoxylated (especially ethoxylated or propoxylated) trimethylolpropane triacrylate, alkoxylated (especially ethoxylated or propoxylated) trimethylolpropane trimethacrylate, alkoxylated (especially ethoxylated or propoxylated) glycerol triacrylate, pentaerythritol, The alkoxylated (particularly ethoxylated or propoxylated) glycerol triacrylate, pentaerythritol triacrylate, alkoxylated (particularly ethoxylated or propoxylated) pentaerythritol triacrylate, and mixtures thereof are preferably selected from the group consisting of trimethylolpropane triacrylate, alkoxylated (particularly ethoxylated or propoxylated) trimethylolpropane triacrylate, alkoxylated (particularly ethoxylated or propoxylated) glycerol triacrylate, pentaerythritol triacrylate, and mixtures thereof.

[0053]

[0053] The one or more tetra(meth)acrylate monomers described herein are preferably selected from the group consisting of ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, alkoxylated (e.g., ethoxylated and propoxylated) pentaerythritol tetra(meth)acrylate, and mixtures thereof, and are preferably selected from the group consisting of ditrimethylolpropane tetra(meth)acrylate, alkoxylated pentaerythritol tetra(meth)acrylate, and mixtures thereof.

[0054]

[0054] The UV-curable security ink composition described herein may further comprise one or more (meth)acrylate-modified vinyl ethers (e.g., VEEA (registered trademark), 2-(2-vinyloxyethoxy)ethyl acrylate (CAS number 86273-46-3)).

[0055]

[0055] Examples of free radical photoinitiators are known to those skilled in the art and are preferably selected from the group consisting of aminoketone compounds (e.g., alpha-aminoketone compounds), hydroxyketone compounds (e.g., alpha-hydroxyketone compounds), alkoxyketone compounds (e.g., alpha-alkoxyketone compounds), acetophenone compounds, benzophenone compounds, ketosulfone compounds, benzil ketal compounds, benzoin ether compounds, glyoxylate compounds, phosphine oxide compounds, and mixtures thereof, preferably selected from the group consisting of phosphine oxide compounds.

[0056]

[0056] The UV-curable security ink composition described herein comprises from about 0.1 to about 20 wt. %, preferably from about 1 to about 15 wt. %, of at least one free-radical photoinitiator described herein, the weight percentages being based on the total weight of the UV-curable security ink composition.

[0057] Suitable examples of alpha-aminoketone compounds include those containing a benzoyl moiety, also known as alpha-aminoacetophenone, such as 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one (CAS No. 71868-10-5); 2-benzyl-2-dimethylamino-1-(4-morpholino-phenyl)-butan-1-one (CAS No. 119313-12-1); and 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one (CAS No. 119344-86-4).

[0058] Suitable examples of alpha-hydroxy ketones include, but are not limited to, 2-hydroxy-2-methylpropiophenone (CAS No. 7473-98-5); 2-hydroxy-2-methyl-1-(4-tert-butyl)phenylpropan-1-one (CAS No. 68400-54-4); 2-hydroxy-4'-hydroxyethoxy-2-methylpropiophenone (CAS No. 106797-53-9); 2-hydroxy-1-[4-[4-(1-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-1-one (CAS No. 474510-57-1); (1-hydroxycyclohexyl)phenylmethanone (CAS No. 947-19-3); 2-hydroxy-1-[4-[4-(1-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-1-one (CAS No. 474510-57-1); (1-hydroxycyclohexyl)phenylmethanone (CAS No. 947-19-3); 1-[2,3-dihydro-1-[4-(1-hydroxy-2-methyl-1-oxopropyl)phenyl]-1,3,3-trimethyl-1H-inden-5-yl]-2-hydroxy-2-methyl-1-propanone (CAS No. 135452-43-6); ar-(1-hydroxy-2-methyl-1-oxopropyl)(1-methylethenyl)-benzene homopolymer (CAS No. 163702-01-0); α-(1,1-dimethyl-2-oxo-2-phenylethyl)-ω-hydroxy-poly(oxy-1,2-ethanediyl)(9CI) (CAS No. 554449-21-7); polymeric alpha-hydroxy-ketone (CAS No. 1842314-75-3); or mixtures thereof.

[0059] Suitable examples of acetophenones include, but are not limited to, 2,2-diethoxyacetophenone (CAS No. 6175-45-7); 2-ethylhexyl-4-dimethylaminobenzoate (CAS No. 21245-02-3); and 2-methoxy-2-phenylacetophenone (CAS No. 3524-62-7).

[0060] Suitable examples of benzophenone compounds include, but are not limited to, benzophenone (CAS No. 119-61-9); polymeric benzophenone derivatives; 2-methylbenzophenone (CAS No. 131-58-8); 3-methylbenzophenone (CAS No. 643-65-2); 4-methylbenzophenone (CAS No. 134-84-9); 2,4,6-trimethylbenzophenone (CAS No. 954-16-5); 3,3'-dimethyl-4-methoxybenzophenone (CAS No. 41295-28-7); 4 4-phenylbenzophenone (CAS No. 2128-93-0); 4-chlorobenzophenone (CAS No. 134-85-0); 4,4'-bis(diethylamino)benzophenone (CAS No. 90-93-7); methyl-2-benzoylbenzoate (CAS No. 606-28-0); 4-(4-methylphenylthio)benzophenone (CAS No. 83846-85-9); 4-hydroxybenzophenone laurate (CAS No. 142857-24-7), and a mixture of 50% benzophenone (CAS No. 119-61-9) and 50% 1-hydroxycyclohexyl phenyl ketone (CAS No. 947-19-3).

[0061]

[0061] Suitable examples of ketosulfone compounds include, but are not limited to, 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-(4-methylphenylsulfonyl)propan-1-one (CAS number 272460-97-6).

[0062] Suitable examples of benzyl ketal compounds include, but are not limited to, 2,2-dimethoxy-2-phenylacetophenone (CAS number 24650-42-8).

[0063]

[0063] Suitable examples of benzoin ethers include, but are not limited to, 2-ethoxy-1,2-diphenylethanone (CAS No. 574-09-4); 2-isopropoxy-1,2-diphenylethanone (CAS No. 6652-28-4); 2-isobutoxy-1,2-diphenylethanone (CAS No. 22499-12-3); 2-butoxy-1,2-diphenylethanone (CAS No. 22499-11-2); 2,2-dimethoxy-1,2-diphenylethanone (CAS No. 24650-42-8); and 2,2-diethoxyacetophenone (CAS No. 6175-45-7).

[0064] Suitable examples of glyoxylate compounds include, but are not limited to, 2-oxo-2-phenylacetic acid methyl ester (CAS No. 15206-55-0); 2-[2-oxo-2-phenyl-acetoxy-ethoxy]ethyl 2-oxo-2-phenylacetate (CAS No. 211510-16-6); oxy-phenylacetic acid 2-[2-hydroxy-ethoxy]-ethyl ester (CAS No. 442536-99-4); α-(1-oxo-2-phenyl)acetic acid methyl ester (CAS No. 15206-55-0); 2-[2-oxo-2-phenyl-acetoxy-ethoxy]ethyl 2-oxo-2-phenylacetate (CAS No. 211510-16-6); hydroxy-phenylacetic acid 2-[2-hydroxy-ethoxy]-ethyl ester (CAS No. 442536-99-4); α-(1-oxo-2-phenyl)acetic acid methyl ester (CAS No. 442536-99-4); and mixtures thereof; more preferably, 2-oxo-2-phenylacetic acid methyl ester (CAS number 15206-55-0); 2-[2-oxo-2-phenyl-acetoxy-ethoxy]ethyl 2-oxo-2-phenylacetate (CAS number 211510-16-6); or mixtures thereof.

[0065] Suitable examples of phosphine oxide compounds include, but are not limited to, (1,4,6-trimethylbenzoyl)diphenylphosphine oxide (CAS No. 75980-60-8); 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide (CAS No. 84434-11-7); phenyl-bis(2,4,6-trimethylbenzoyl)phosphine oxide (CAS No. 162881-26-7); bis(1,6-di Methoxybenzoyl)(1,4,4-trimethylpentyl)phosphine oxide (CAS No. 145052-34-2); Ethyl (3-benzoyl-2,4,6-trimethylbenzoyl)(phenyl)phosphinate (CAS No. 1539267-56-5); α,α',α''-1,2,3-propanetriyltris[ω-[[phenyl(1,4,6-trimethylbenzoyl)phosphinyl]oxy]-poly(oxy-1,2-ethanediyl)(CAS 1834525-17-5); or mixtures thereof, such as a mixture of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (CAS No. 75980-60-8) and 2-hydroxy-2-methylpropiophenone (CAS No. 7473-98-5), a mixture of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (CAS No. 162881-26-7) and 2-hydroxy-2-methylpropiophenone (CAS No. 7473-98-5); and a mixture of ethyl (2,4,6-trimethylbenzoyl)phenylphosphinate (CAS No. 84434-11-7) and 2-hydroxy-2-methylpropiophenone (CAS No. 7473-98-5).

[0066] In embodiments where the UV curable security ink composition comprises one or more cationically curable compounds, the ink composition comprises a cationic photoinitiator.

[0067]

[0067] Examples of various useful photoinitiators can be found in standard textbooks, such as "Chemistry & Technology of UV & EB Formulation for Coatings, Inks & Paints", Volume 3, "Photoinitiators for Free Radical Cationic and Anionic Polymerization", 2nd Edition, by JV Crivello & K. Dietliker, edited by G. Bradley, published by John Wiley & Sons in collaboration with SITA Technology Limited in 1998.

[0068]

[0068] To achieve efficient curing, it may be advantageous to include at least one photosensitizer in combination with one or more photoinitiators, said sensitizer being preferably a thioxanthone compound. Suitable examples of sensitizers include, but are not limited to, 2-methylthioxanthone (CAS No. 15774-82-0); 2-isopropyl-9H-thioxanthen-9-one (CAS No. 5495-84-1); 4-(1-methylethyl)-9H-thioxanthen-9-one (CAS No. 83846-86-0); 2,4-diethyl-9H-thioxanthen-9-one (CAS No. 82799-44-8); 2-chloro-9H-thioxanthen-9-one (CAS No. 86-39-5); 1-chloro-9H-thioxanthen-9-one (CAS No. 86-39-5); -4-Propoxy-9H-thioxanthen-9-one (CAS number 142770-42-1); 1,3-di[[α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]]oxy]-2,2-bis[[α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]]oxymethylpropane (CAS number 1003567-83-6); α-[2-[(9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]]oxymethylpropane 2-[2-[1-[2-[[2-(9-oxothioxanthen-2-yl)oxyacetyl]amino]-3-[1-[2-(2-prop-2-enoyloxyethoxy)ethoxy]ethoxy]-2-[1-[2-(2-prop-2-enoyloxyethoxy)ethoxy]ethoxymethyl]propionyl]-2-[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]oxy]-2-[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]oxy]-2-[2-[(9-oxothioxanthen-2-yl)oxyacetyl]amino]-3-[1-[2-(2-prop-2-enoyloxyethoxy)ethoxy]ethoxymethyl]propionyl] [oxy]ethoxy]ethoxy]ethyl prop-2-enoate (CAS No. 1427388-03-1); α-[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]-ω-[[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]oxy]-poly(oxy-1,4-butanediyl) (CAS No. 813452-37-8); oligomeric and polymeric compounds thereof (CAS Nos. 515139-51-2 and 2055335-46-9); and mixtures thereof.

[0069]

[0069] When present, the at least one photosensitizer is preferably present in an amount of from about 0.1 wt % to about 2 wt %, more preferably from about 0.2 wt % to about 1 wt %, the weight percentages being based on the total weight of the UV curable security ink composition.

[0070]

[0070] The UV curable security ink compositions described herein may further comprise one or more co-sensitizers comprising an aliphatic or aromatic tertiary amine, which may be triethylamine, N,N-dimethylethanolamine, N-methyl-diethanolamine, triethanolamine, 2-(dimethylamino)ethylbenzoate, ethyl-4-dimethylaminobenzoate, 2-ethylhexyl-4-dimethylaminobenzoate, isoamyl-4-dimethylaminobenzoate, butoxyethyl-4-dimethylaminobenzoate, amino-modified acrylate resins, or oligomeric aminobenzoates.

[0071]

[0071] The UV-curable security ink compositions described herein may further comprise one or more cationically curable compounds and one or more cationic photoinitiators. Cationically curable compounds cure by a cationic mechanism, which typically involves activation by irradiation of one or more compounds that liberate cationic species, such as acids, which then initiate curing to react and / or crosslink monomers and / or oligomers, thereby solidifying the coating composition. Preferably, the one or more cationically curable compounds are selected from the group consisting of vinyl ethers, propenyl ethers, cyclic ethers such as epoxides, oxetanes, glycidyl ethers, and tetrahydrofuran, lactones, cyclic thioethers, vinyl thioethers, propenyl thioethers, hydroxyl-containing compounds, and mixtures thereof; preferably, the cationically curable compounds are selected from the group consisting of vinyl ethers, propenyl ethers, cyclic ethers such as epoxides, oxetanes, and tetrahydrofuran, lactones, and mixtures thereof; more preferably, the cationically curable compounds are selected from the group consisting of vinyl ethers, cyclic ethers such as epoxides, oxetanes, and tetrahydrofuran, and mixtures thereof. Typical examples of cationic photoinitiators include iodonium salts, particularly diaryliodonium salts, oxonium salts, particularly triaryloxonium salts, sulfonium salts, particularly diarylsulfonium salts, and mixtures thereof.

[0072]

[0072] The UV-curable security ink composition described herein may further comprise at least one colorant, such as a pigment or dye. In the present invention, a pigment is a colorant that is insoluble or slightly soluble in the ink composition, and a dye is completely soluble in the ink composition. Preferably, the at least one colorant is an IR-transparent organic pigment or an IR-transparent organic dye. It is preferred that the pigment or dye contained is transparent in the IR region, especially the near-IR region, because this allows the ink composition to further incorporate specific IR-absorbing agents in order to enhance the anti-counterfeiting resistance of the security feature.

[0073] Suitable organic pigments include, but are not limited to, CI Pigment Yellow 12, CI Pigment Yellow 24, CI Pigment Yellow 42, CI Pigment Yellow 93, CI Pigment 109, CI Pigment Yellow 110, CI Pigment Yellow 138, CI Pigment Yellow 139, CI Pigment Yellow 147, CI Pigment Yellow 150, CI Pigment Yellow 155, CI Pigment Yellow 173, CI Pigment Yellow 185; CI Pigment Orange 34, CI Pigment Orange 48, CI Pigment Orange 49, CI Pigment Orange 61, CI Pigment Orange 71, CI Pigment Orange 73; CI Pigment Orange 77; CI Pigment Red 9, CI Pigment Red 22, CI Pigment Red 23, CI Pigment Red 67, CI Pigment Red 122, CI Pigment Red 144, CI Pigment Red 146, CI Pigment Red 168, CI Pigment Red 170, CI Pigment Red Pigment Red 177, CI Pigment Red 178, CI Pigment Red 179, CI Pigment Red 185, CI Pigment Red 189, CI Pigment Red 190, CI Pigment Red 194, CI Pigment Red 195, CI Pigment Red 196, CI Pigment Red 202, CI Pigment Red 224, CI Pigment Red 242, CI Pigment Red 254, CI Pigment Red 255, CI Pigment Red 264; CI Pigment Brown 23 , CI Pigment Brown 25, CI Pigment Brown 30, CI Pigment Blue 15, CI Pigment Blue 15:3, CI Pigment Blue 22, CI Pigment Blue 60, CI Pigment Blue 64, CI Pigment Blue 65, CI Pigment Violet 19, CI Pigment Violet 23, CI Pigment Violet 31, C. Pigment Violet 32, CI Pigment Violet 33, CI Pigment Violet 37, CI Pigment Green 7, CIPigment Green 36, CI Pigment Green 47, CI Pigment Green 54, CI Pigment Black 31, CI Pigment Black 32, CI Pigment White 4, CI Pigment White 6, CI Pigment White 21, and CI Pigment White 22, or mixtures thereof.

[0074] Suitable organic dyes include, but are not limited to, CI Solvent Yellow 19, CI Solvent Yellow 79, CI Solvent Yellow 81, CI Solvent Yellow 82, CI Solvent Yellow 88, CI Solvent Orange 45, CI Solvent Orange 54, CI Solvent Orange 56, CI Solvent Orange 99, CI Solvent Red 8, CI Solvent Red 119, CI Solvent Red 122, CI Solvent Red 127, CI Solvent Red 130, CI Solvent Red 160, CI Solvent Red 233, CI Solvent Green 7, CI Solvent Blue 67, CI Solvent Blue 70, CI Solvent Brown 27, CI Solvent Brown 43, CI Solvent Brown 44, CI Solvent Black 27, CI Solvent Black 28, and CI Solvent Black 29, or mixtures thereof.

[0075]

[0075] In embodiments where the UV-curable security ink composition described herein lacks said at least one colorant (i.e., the composition comprises about 0 wt. % of said at least one colorant), said UV-curable security ink composition preferably comprises at least one compound P described herein in a total amount of about 0.005 wt. % to about 0.2 wt. %, where wt. % is based on the total weight of the UV-curable security ink composition.

[0076]

[0076] In embodiments where the UV-curable security ink composition described herein comprises said at least one colorant in an amount of from about 0.1 wt % to about 20 wt %, preferably from about 0.5 wt % to about 10 wt %, said UV-curable security ink composition preferably comprises at least one compound P described herein in a total amount of from about 0.1 wt % to about 1.0 wt %, the wt % being based on the total weight of the UV-curable security ink composition.

[0077] The UV-curable security ink compositions described herein may further comprise at least one additive, including, but not limited to, compounds and materials used to adjust the physical, rheological, and chemical parameters of the composition, such as viscosity, consistency, UV stability, adhesive properties, antistatic properties, storage stability, etc. The additives described herein may be present in the coating composition in amounts and forms known in the art, including so-called nanomaterials, in which at least one of the additive's dimensions is in the range of 1 to 1000 nm. The one or more additives are preferably compatible with or dispersible in the UV-curable security ink composition, i.e., do not phase separate from the remainder of the composition during storage.

[0078] Examples of additives include surfactants, which may be fluorosurfactants, siloxanes, silicones, silanols, polyoxyalkyleneamines, propoxylated (poly(oxypropylene))diamines, alkyl ether amines, nonylphenol ethoxylates, ethoxylated fatty amines, quaternized copolymers of vinylpyrrolidone and dimethylaminoethyl methacrylate, fluorinated organic acid diethanolamine salts, alkoxylated ethylenediamines, polyethylene oxides, polyoxyalkylenepolyalkylenepolyamineamines, polyoxyalkylenepolyalkylenepolyimines, alkylphosphate ethoxylate mixtures, polyoxyalkylene derivatives of propylene glycol, polyoxyethylated fatty alcohols, or mixtures thereof. The surfactant additive may be present in an amount of about 0.01 wt % to about 1.0 wt %, the weight percentage being based on the total weight of the UV-curable security ink composition.

[0079] The UV-curable security ink composition described herein does not contain any volatile components, such as organic solvents. However, it may be advantageous in some cases to incorporate a small amount of one or more organic solvents to improve adhesion to the substrate surface after UV curing. In this case, the one or more organic solvents added can be in any amount within the range that does not cause solvent resistance and VOC problems, preferably from about 0.1% to about 5.0% by weight, where the weight percentage is based on the total weight of the UV-curable security ink composition.

[0080]

[0080] The UV curable security ink compositions described herein are particularly suitable for application to a substrate, such as a substrate described herein, preferably by a printing process selected from the group consisting of a screen printing process, a rotogravure process, a flexographic process, and a non-contact fluid micro-dispensing process, more preferably by a non-contact fluid micro-dispensing process.

[0081] Screen printing (also known in the art as silk-screen printing) is a stenciling process in which ink is transferred to a surface through a stencil supported on a mesh of fine silk, synthetic, or metal threads tightly stretched over a frame. The holes in the mesh are blocked in the non-image areas and left open in the image areas; the image carrier is called the screen. Screen printing can be flatbed or rotary. During printing, ink is supplied to the frame, flooding the screen, which is then squeegeeed across it, forcing the ink through the openings in the screen. At the same time, the surface to be printed is held in contact with the screen, transferring the ink to it. Screen printing is further described, for example, in *The Printing Ink Manual*, R.H. Leech and R.J. Pierse, Springer Edition, 5th Edition, pp. 58-62, and *Printing Technology*, J.M.Adams and P.A. Dolin, Delmar Thomson Learning, 5th Edition, pp. 293-328.

[0082] As known to those skilled in the art, the term rotogravure refers to a printing process described, for example, in "Handbook of print media," Helmut Kipphan, Springer Edition, p. 48. Rotogravure is a printing process in which image elements are engraved into the surface of a cylinder. The non-image areas are an unchanged first level. Before printing, the entire printing plate (non-printing and printing elements) is inked and saturated with ink. Before printing, a wiper or blade removes the ink from the non-image areas, leaving ink only in the cells. The image is transferred from the cells to the substrate by pressure, typically in the range of 2-4 bar, and adhesive forces between the substrate and the ink. The term rotogravure does not encompass, for example, intaglio printing processes (also known in the art as engraved steel die or copperplate printing processes), which rely on different types of ink.

[0083]

[0083] Flexographic printing preferably uses a unit equipped with a chambered doctor blade, an anilox roller, and a plate cylinder. The anilox roller advantageously has small cells, the volume and / or density of which determine the speed of protective varnish application. The chambered doctor blade lies on the anilox roller, filling the cells and simultaneously scraping off excess protective varnish. The anilox roller transfers the ink to the plate cylinder, which ultimately transfers the ink to the substrate. The plate cylinder can be made of a polymer or elastomeric material. Polymers are primarily used as photopolymers for the plate, and sometimes as seamless coatings for sleeves. Photopolymer plates are made of photosensitive polymers that harden under ultraviolet (UV) light. The photopolymer plate is cut to the required size and placed in a UV light exposure unit. One side of the plate is fully exposed to UV light to solidify or harden the base of the plate. The plate is then turned over, a job negative is attached to the unhardened side, and the plate is further exposed to UV light. This solidifies the plate in the image area. The plate is then treated to remove unsolidified photopolymer from the non-image areas, thereby lowering the plate surface in the non-image areas. After treatment, the plate is dried and given a post-exposure dose of UV light to harden the entire plate. Preparation of plate cylinders for flexography is described in Printing Technology, J.M.A. Dams and P.A. Dolin, Delmar Thomson Learning, 5th Edition, pp. 359-360.

[0084] Depending on the printing process selected to produce the security features described herein, suitable viscosity values ​​of the UV-curable security ink composition are used, with screen printing inks having a viscosity of about 50 mPa·s to about 3000 mPa·s at 25°C, flexographic inks having a viscosity of about 50 mPa·s to about 2000 mPa·s at 25°C, and rotogravure inks having a viscosity of about 50 mPa·s to about 1000 mPa·s at 25°C, and viscosity measurements of security inks having viscosity values ​​of 100 mPa·s to 3000 mPa·s are performed using a Brookfield viscometer (model "RVDV-I"). The viscosity of the security inks with viscosity values ​​between 10 mPa·s and 100 mPa·s was measured using a TA Instruments rotational viscometer DHR-2 with a cone-plane geometry and a diameter of 40 mm at 25°C and 1000 s. The spindle and rotation speed (rpm) were adjusted according to the following viscosity ranges: 100-500 mPa·s with a 100 rpm spindle 21; 500-2500 mPa·s with a 100 rpm spindle 27; and 50 rpm with a 500-3000 mPa·s spindle 27. The viscosity of the security inks with viscosity values ​​between 10 mPa·s and 100 mPa·s was measured using a TA Instruments rotational viscometer DHR-2 with a cone-plane geometry and a diameter of 40 mm at 25°C and 1000 s. -1 The viscosity is measured using a DIN 4'' cup or a Brookfield DV1 LV viscometer equipped with an LV1 spindle at 0.3 to 60 rpm and a temperature of 45°C.

[0085]

[0085] The non-contact fluid micro-dispensing process described herein is preferably selected from the group consisting of spray coating, aerosol jet printing, electrohydrodynamic printing, slot die coating, and inkjet printing, more preferably by an inkjet printing process, said non-contact fluid micro-dispensing printing process being a variable information printing method that allows for the unique production of the security features described herein. The application process is selected as a function of the design and resolution of the security features to be produced.

[0086] Spray coating is a technique that involves forcing a composition through a nozzle, thereby forming a fine aerosol. A carrier gas and electrostatic charging may be involved to help direct the aerosol toward the surface to be printed. Spray printing makes it possible to print spots and lines. Compositions suitable for spray printing typically have a viscosity of about 10 mPa·s to about 1 Pa·s (at 25°C, 1000 s -1 ) The resolution of spray coating printing is in the millimeter range. Spray printing is described, for example, in F.C. K. Rebs, Solar Energy Materials & Solar Cells (2009), 93, 407.

[0087] Aerosol jet printing (AJP) is an emerging non-contact direct-write technique aimed at producing fine features on a wide range of substrates. AJP is compatible with a wide range of materials and freeform deposition, allowing high resolution (on the order of about 10 micrometers) with relatively large standoff distances (e.g., 1-5 mm) in addition to orientation independence. This technique uses either ultrasonic or pneumatic atomizers to produce a thin film of a viscous liquid typically between about 1 mPa·s and about 1 Pa·s (at 25°C, 1000 s). -1 Aerosol jet printing is described, for example, in NJ Wilkinson et al., The International Journal of Advanced Manufacturing Technology (2019) 105:4599-4619.

[0088] Electrohydrodynamic inkjet printing is a high-resolution inkjet printing technique. Electrohydrodynamic inkjet printing uses an externally applied electric field to manipulate droplet size, ejection frequency, and placement on the substrate to achieve higher resolution than conventional inkjet printing while maintaining high production rates. The resolution of electrohydrodynamic inkjet printing is approximately two orders of magnitude higher than conventional inkjet printing techniques, and therefore electrohydrodynamic inkjet printing can be used to define nano- and microscale patterns. Electrohydrodynamic inkjet printing can be used in both DOD and continuous modes. Compositions for electrohydrodynamic inkjet printing typically have a viscosity of about 1 mPa·s to about 1 Pa·s (at 25°C, 1000 s). -1 Electrohydrodynamic inkjet printing techniques are described, for example, in PV Raje and NC Murmu, International Journal of Emerging Technology and Advanced Engineering, (2014), 4(5), pp. 174-183.

[0089] Slot die coating is a one-dimensional coating technique. Slot die coating allows for the coating of stripes of material, and is well suited to producing multilayer coatings in which stripes of different materials are layered on top of each other. Pattern registration is achieved by moving the coating head along a direction perpendicular to the direction of web movement. A slot die coating head includes a mask that defines slots in the coating head through which the slot die coating ink is dispersed. An example of a slot die coating head is shown in F.C.K.rebs, Solar Energy Materials & Solar Cells (2009), 93, pp. 405-406. Compositions suitable for slot die coating typically have a viscosity of about 1 mPa·s to about 20 Pa·s (at 25°C, 1000 s -1 )

[0090] According to one embodiment, the UV-curable security ink compositions described herein are printed by an inkjet printing process, preferably a continuous inkjet (CI) printing process or a drop-on-demand (DOD) inkjet printing process, more preferably a drop-on-demand (DOD) inkjet printing process. Drop-on-demand (DOD) printing is a non-contact printing process in which droplets are generated only when needed for printing, generally by an ejection mechanism rather than by unstable jets. Depending on the mechanism used in the printhead to generate the droplets, DOD printing can be performed using a variety of inkjet printing methods, including piezo impulse, thermal jet, valve jet (viscosity of about 1 mPa·s to about 1 Pa·s at 25°C, 1000 s), and other inkjet printing methods. -1 Typically, DOD inkjet printing ink compositions suitable for piezo and thermal DOD inkjet printing have a viscosity of less than 30 mPa·s at 25°C.

[0091]

[0091] The viscosity of the UV-curable security ink composition described herein can be adjusted by varying the ratio between one or more radically curable monomers and / or one or more radically curable oligomers described herein.

[0092]

[0092] The security features described herein are made by a method comprising the steps of: a) applying, preferably printing, a UV-curable security ink composition described herein; and b) at least partially curing the UV-curable security ink composition from step a).

[0093]

[0093] The UV curable security ink compositions described herein are particularly suitable for application to a substrate, such as a substrate as described herein, preferably by a printing process selected from the group consisting of a pad printing process, a screen printing process, a rotogravure process, a flexographic process, and a non-contact fluid micro-dispensing process, more preferably a non-contact fluid micro-dispensing process as described herein, and even more preferably an inkjet printing process.

[0094] The method described herein includes step b) of at least partially curing the UV-curable security ink composition from step a), wherein the curing step is performed using a curing unit. Suitable curing units include UV curing units equipped with a light-emitting diode (LED) lamp or an arc discharge lamp, such as a medium-pressure mercury arc (MPMA) or a metal vapor arc lamp, as a source of actinic radiation. According to one embodiment, the curing unit is a UV-Vis light-emitting diode (LED) curing unit. In contrast to medium-pressure mercury lamps, which have emission bands in the UV-A, UV-B, and UV-C regions of the electromagnetic spectrum, UV-LED lamps emit radiation in the UV-A region, e.g., in the range of about 380 nm to about 410 nm. Furthermore, current UV-LED lamps emit quasi-monochromatic radiation, i.e., they emit only at one wavelength, e.g., 365 nm, 385 nm, 395 nm, or 405 nm.

[0095] According to one embodiment, step b) of at least partially curing the UV-curable security ink composition described herein comprises exposing said composition to one or more wavelengths between about 360 nm and about 410 nm emitted by one or more UV-LED curing units to form security features. Preferably, step b) described herein comprises exposing the UV-curable security ink composition to a single wavelength between 365 nm and 420 nm, e.g., 365 nm, 385 nm, 395 nm, or 405 nm, emitted by a UV-LED source to form security features. The UV-curable security ink composition preferably has a curing intensity of at least 150 mJ / cm. 2 and more preferably 200 mJ / cm 2 The UV curable security ink composition is cured to form the security feature by exposure to UV light at the above dose, and the dose can be measured using a UV Power Puck® II radiometer from EIT, Inc., USA.

[0096]

[0096] The present invention further provides a security feature obtainable by the method of making a security feature described herein. The present invention further provides a security feature made with a UV-Vis curable security ink described herein, preferably a UV-Vis curable continuous inkjet (CI) or drop-on-demand (DOD) inkjet printed security ink, on a substrate described herein.

[0097] According to one embodiment, the security features described herein comprise one or more indicia. As used herein, the term "indicia" is intended to mean continuous and discontinuous layers of distinguishable markings or labels or patterns. Preferably, the one or more indicia described herein are selected from the group consisting of codes, symbols, alphanumeric symbols, motifs, geometric patterns (e.g., circles, triangles, and regular or irregular polygons), letters, words, numbers, logos, drawings, portraits, and combinations thereof. Examples of codes include coding marks, such as encoded alphanumeric data, one-dimensional barcodes, two-dimensional barcodes, QR codes, data matrices, and IR-readable codes. The one or more indicia (x30) described herein may be solid and / or raster indicia.

[0098]

[0098] The substrate for the security features described herein is preferably selected from the group consisting of paper or other fibrous materials (including woven and nonwoven fibrous materials), such as cellulose, paper-containing materials, glass, metal, ceramic, plastics and polymers, metallized plastics or polymers, composite materials, and mixtures or combinations of two or more thereof. Typical paper, paper-like, or other fibrous materials are made from a variety of fibers, including, but not limited to, abaca, cotton, hemp, wood pulp, and blends thereof. As is well known to those skilled in the art, cotton and cotton / hemp blends are preferred for banknotes, while wood pulp is commonly used for non-banknote security documents. Typical examples of plastics and polymers include polyolefins, such as polyethylene (PE) and polypropylene (PP), such as biaxially oriented polypropylene (BOPP), polyamides, polyesters, such as poly(ethylene terephthalate) (PET), poly(1,4-butylene terephthalate) (PBT), poly(ethylene 2,6-naphthoate) (PEN), and polyvinyl chloride (PVC). Spunbond olefin fibers, such as those sold under the trademark Tyvek®, can also be used as the substrate. Typical examples of metallized plastics or polymers include the above-mentioned plastic or polymer materials having a metal disposed continuously or discontinuously on their surfaces. Typical examples of metals include, but are not limited to, aluminum, chromium, copper, gold, silver, alloys thereof, and combinations of two or more of the aforementioned metals. Metallization of the above-mentioned plastic or polymer materials can be achieved by electrodeposition, high-vacuum coating, or sputtering processes. Typical examples of composite materials include, but are not limited to, multilayer structures or laminates of paper and at least one plastic or polymer material, such as those mentioned above, as well as plastic and / or polymer fibers incorporated into paper-like or fibrous materials, such as those mentioned above. Of course, the substrate can contain additional additives known to those skilled in the art, such as fillers, sizing agents, whitening agents, processing aids, reinforcing agents, or wet strength agents.

[0099] The present invention further provides a security document comprising a substrate as described herein and a security feature as described herein, or a security document comprising more than one of the security features as described herein. Security documents include, but are not limited to, value documents and valuable goods. Typical examples of value documents include, but are not limited to, banknotes, certificates, tickets, checks, vouchers, fiscal stamps and tax labels, contracts, and the like, identification documents such as passports, identity cards, visas, driver's licenses, bank cards, credit cards, transaction cards, access documents or cards, admission tickets, public transport tickets, or title deeds, and the like. The term "valuable goods" refers to packaging, particularly packaging for the pharmaceutical, cosmetic, electronics, or food industries, that can be protected from counterfeiting and / or unauthorized duplication to ensure the contents of the package, such as, for example, authentic drugs. Examples of such packaging include, but are not limited to, labels, such as authentication brand labels, tamper-evident labels, and seals. Preferably, the security document described herein is selected from the group consisting of a banknote, an identification card, an entitlement document, a driver's license, a credit card, an access card, a transportation title deed, a ticket, and a secure product label. Alternatively, the security features described herein may be fabricated into a secondary substrate, such as a security thread, a security stripe, a foil, a decal, a window, or a label, and then transferred to the security document in a separate step.

[0100]

[0100] In order to further increase the security level of the security document and its resistance to counterfeiting and unauthorized duplication, the substrates described herein may include printed, coated, or laser marked or laser perforated indicia, watermarks, security threads, fibers, planchettes, luminescent compounds, windows, foils, transfer stickers, primers, and combinations of two or more thereof.

[0101]

[0101] One or more protective layers may be applied over the security features or security documents described herein in order to improve the security document's resistance to dirt or chemicals, and its cleanability, and therefore its durability throughout its shelf life, or to modify its aesthetic appearance (e.g., optical gloss). If present, the protective layer(s) are typically made of a protective varnish, which may be clear, or may be slightly pigmented or tinted, and may have some gloss. The protective varnish may be a radiation-curable composition, a heat-drying composition, or any combination thereof. Preferably, the protective layer(s) are made of a radiation-curable, more preferably a UV-Vis-curable composition.

[0102]

[0102] The security features described herein may be applied directly to a substrate where they will remain permanently (e.g., for banknote applications). Alternatively, the security features may be applied to a temporary substrate from which the security features are subsequently removed for fabrication purposes. The temporary substrate may then be removed from the security features after solidifying / curing the UV-Vis radiation radically curable security ink described herein, preferably a UV-Vis radiation radically curable screen-printed security ink, to produce the security features.

[0103] Alternatively, in another embodiment, an adhesive layer may be present on the security feature or on the substrate containing the security feature, with the adhesive layer being on the side of the substrate opposite the side on which the security feature is provided, or on the same side as the security feature. Thus, the adhesive layer may be applied to the security feature or the substrate, with the adhesive layer being applied after the curing step is complete. Such articles can be attached to all kinds of documents or other articles or items without printing or other processes requiring machines and significant labor. Alternatively, the substrates described herein containing the security features described herein may be in the form of transfer foils, which can be applied to documents or articles in a separate transfer step. For this purpose, a release coating is applied to the substrate, and the security features described herein are fabricated thereon. One or more adhesive layers may be applied to the security features thus fabricated.

[0104] Also described herein are substrates, security documents, decorative elements, and objects that include more than one security feature as described herein, i.e., two, three, four, etc. Also described herein are articles, particularly security documents, decorative elements, or objects, that include the security features described herein.

[0105]

[0105] As mentioned above, the security features described herein can be used to protect and authenticate security documents or decorative elements.

[0106]

[0106] Typical examples of decorative elements or objects include, but are not limited to, luxury goods, cosmetic packaging, automobile parts, electronic / electrical appliances, furniture, and fingernail articles.

[0107]

[0107] Security documents include, but are not limited to, valuable documents and valuable goods. Typical examples of valuable documents include, but are not limited to, banknotes, certificates, tickets, checks, vouchers, fiscal and tax stamps, contracts, and the like; identification documents, such as passports, identity cards, visas, driver's licenses, bank cards, credit cards, transaction cards, access documents or cards, admission tickets, public transport tickets, academic certificates, or title deeds, preferably banknotes, identity cards, title deeds, driver's licenses, and credit cards. The term "valuable goods" refers to packaging, especially packaging for cosmetics, dietary supplements, pharmaceuticals, alcohol, tobacco products, beverages or food, electrical / electronic products, textiles, or jewelry, i.e., packaging for goods to be protected from counterfeiting and / or unauthorized duplication to ensure the contents of the package, such as, for example, drugs, are authentic. Examples of such packaging include, but are not limited to, labels, such as authentication brand labels, tamper-evident labels, and seals. It is noted that the disclosed substrates, value documents, and value items are presented for illustrative purposes only, without limiting the scope of the present invention.

[0108]

[0108] Those skilled in the art may envision several modifications to the specific embodiments described above without departing from the spirit of the present invention, and such modifications are encompassed by the present invention.

[0109]

[0109] Furthermore, all documents referred to throughout this specification are hereby incorporated by reference in their entirety as if fully set forth herein.

[0110] [Example] The present invention will now be described in more detail with reference to non-limiting examples. The following examples provide more details regarding the preparation of the UV-curable security ink compositions described herein, as well as the fluorescence intensity and light fastness of machine-readable security features made therefrom.

[0111]

[0111] The UV-curable security ink compositions E1 to E3 and C1 to C6 are inks that do not contain a colorant, and the UV-curable security ink compositions E4 to E6 and C7 to C12 are inks that contain a colorant. Preparation of compounds Mo, Mo', and M1-M9 [ka]

[0112] To a mixture of 5,12-dibromoanthra[2,1,9-def:6,5,10-d'e'f']diisochromene-1,3,8,10-tetraone (3.80 g, 6.91 mmol, 95% purity, containing a mixture of the 5,12-dibromo (Mo), 5-13-dibromo (Mo') isomers and the 5,12,13-tribromo isomer (not shown)) (CAS number 118129-60-5, abcr GmbH) in propionic acid (6.65 g, 6.72 mL) was added 2,6-diisopropylaniline (3.67 g, 20.7 mmol), and the reaction mixture was stirred at 140° C. for 18 hours. It was then cooled to room temperature and poured into 20 mL of 2 M HCl, stirred for 30 minutes, and then filtered. The crude red solid was purified by MPLC chromatography on a Puriflash system (cyclohexane-dichloromethane 4:1) to give 2 g (42% yield) of 5,12-dibromo-2,9-bis(2,6-diisopropylphenyl)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone (CAS: 331861-94-0) as the major product (M1) and 5,13-dibromo-2,9-bis(2,6-diisopropylphenyl)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone (CAS: 861853-33-5) as the by-product (M1'). Purification of the diimide product by chromatography allowed removal of the 5,12,13-tribromo isomer. 1H NMR (400 MHz, CDCl3) δ 9.59 (d, J = 8.1 Hz, 2H), 9.05 (s, 2H), 8.83 (d, J = 8.1Hz, 2H), 7.54 (t, J = 7.8 Hz, 2H), 7.39 (d, J = 7.8 Hz, 4H), 2.76 (septet, J = 6.9 Hz, 4H), 1.22 (d, J = 6.9, 24H). M1' 1 H NMR (400 MHz, CDCl3) δ 9.60 (d, J = 8.1, 2H), 9.05 (s, 2H), 8.84 (d, J = 8.1Hz, 2H), 7.54 (t, J = 7.8 Hz, 2H), 7.39 (d, J = 7.8 Hz, 4H), 2.76 (septet, J = 6.9 Hz, 4H), 1.22 (d, J = 6.9, 24H). 1 The ratio of the 5,12-dibromo (M1) and 5,13-dibromo (M1') isomers was determined to be 3:1, i.e., 75% (M1) and 25% (M1'), by H-NMR. This mixture was used without separation for the synthesis of all derivatives. For simplicity, only the major isomer is mentioned in the following synthesis. [ka]

[0113] To a solution of M1 (2.0 g, 2.30 mmol) in dimethyl sulfoxide (33 mL) were added 4-methoxyphenol (1.72 g, 13.8 mmol) and K2CO3 (1.91 g, 13.8 mmol), and the reaction mixture was stirred at 115 °C for 90 min. The reaction mixture was then poured into 2 M HCl, and the purple precipitate was filtered. The crude product was dissolved in dichloromethane and extracted twice with 1 M NaOH. The combined organic phases were dried over magnesium sulfate, filtered, and concentrated to give 2,9-bis(2,6-diisopropylphenyl)-5,12-bis(4-methoxyphenoxy)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone (M2) as a red solid (2.10 g, 96%).1 H NMR (400 MHz, CDCl3) δ 9.71 (d, J = 8.4 Hz, 2H), 8.73 (d, J = 8.4 Hz, 2H), 8.41 (s, 2H), 7.49 (t, J = 7.8 Hz, 2H), 7.34 (d, J = 7.8 Hz, 4H), 7.20- 7.13 (m, 4H), 7.05-6.98 (m, 4H), 3.87 (s, 6H), 2.74 (septet, J = 6.8 Hz, 4H), 1.22-1.13 (m, 24H). [ka]

[0114] Freshly prepared allyl alcoholate from allyl alcohol (0.33 g, 5.8 mmol) and NaH (0.23 g, wt%, 5.8 mmol) in 3 mL of dimethylformamide was added to a solution of M1 (1.0 g, 1.2 mmol) in dimethylformamide (175 mL) at 20°C under nitrogen with ice-bath cooling. The reaction mixture was stirred for 1 min and rapidly quenched with 200 mL of water. It was then poured into 2 M HCl and stirred at room temperature for 30 min. It was extracted several times with dichloromethane, and the combined organic phases were washed with 1 M NaOH, then dried over magnesium sulfate, filtered, and concentrated. Purification by silica gel column chromatography (100% dichloromethane) gave 5,12-bis(allyloxy)-2,9-bis(2,6-diisopropylphenyl)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone (M3) as a purple solid (0.24 g, 25%). 1H NMR (400 MHz, CDCl3) δ 9.71 (d, J = 8.3 Hz, 2H), 8.73 (d, J = 8.3 Hz, 2H), 8.61 (s, 2H), 7.52 (t, J = 7.8 Hz, 2H), 7.39 (d, J = 7.8 Hz, 4H), 6.38-6.20 (m, 2H), 5.66 (dd, J = 17.3, 1.2 Hz, 2H), 5.51 (dd, J = 10.5, 1.2 Hz, 2H), 5.12 (d, J = 5.5 Hz, 4H), 2.80 (m, J = 6.8 Hz, 4H), 1.22 (d, J = 6.8 Hz, 24H).

[0115] To a solution of M1 (1.0 g, 1.2 mmol) in dimethylformamide (50 ml) under nitrogen was added allylamine (0.66 g, 12 mmol) at room temperature. The reaction mixture was stirred at 20° C. for 30 hours. Another portion of allylamine (0.66 g, 12 mmol) was added and the reaction mixture was heated to 35° C. for 20 hours. The reaction mixture was then poured into 2 M HCl and stirred for 30 minutes. It was extracted several times with dichloromethane and the combined organic phases were washed with 1 M HCl, dried over magnesium sulfate, filtered and concentrated. Purification by silica gel column chromatography (100% dichloromethane) gave 5-(allylamino)-12-bromo-2,9-bis(2,6-diisopropylphenyl)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone (M4) as a green solid (0.16 g, 16%). 1H NMR (400 MHz, CDCl3) δ 9.53 (d, J = 8.2 Hz, 1H), 9.03 (s, 2H), 9.02 (d, J = 8.2 Hz, 1H). 8.75 (d, J = 8.2 Hz, 1H), 8.57 (d, J = 8.1 Hz, 1H), 8.35 (s, 1H), 7.57-7.48 (m, 2H), 7.38 (m, 4H), 6.10 (dd, J = 10.6, 5.5 Hz, 1H), 5.46 (dd, J = 17.2, 1.5 Hz, 1H), 5.38 (dd, J = 10.6, 1.5Hz, 1H), 4.25-4.15 (m, 2H), 2.78 (septet, J = 6.8 Hz, 4H), 1.21 (d, J = 6.8 Hz, 24H). [ka]

[0116] To a solution of M1 (540 mg, 622 μmol) in dimethyl sulfoxide (8.8 ml) was added allyl 4-hydroxybenzoate (665 mg, 3.73 mmol) and potassium carbonate (515 mg, 3.73 mmol) at room temperature, and the reaction mixture was stirred at 115° C. for 30 min. The reaction mixture was then cooled to room temperature, poured into 2 M HCl, and stirred for 30 min. The orange precipitate was filtered, dissolved in dichloromethane, and extracted three times with 1 M NaOH. The combined organic phases were dried over magnesium sulfate, filtered, and concentrated to give diallyl 4,4'-((2,9-bis(2,6-diisopropylphenyl)-1,3,8,10-tetraoxo-1,2,3,8,9,10-hexahydroanthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-5,12-diyl)bis(oxy))dibenzoate (M5) as a red solid (600 mg, 96%). 1H NMR (400 MHz, CDCl3) δ 9.55 (d, J = 8.3 Hz, 2H), 8.73 (d, 8.3 Hz, 2H), 8.48 (s, 2H), 8.16 (d, J = 8.8 Hz, 4H), 8.07 (d, J = 8.8 Hz, 4H), 7.50 (t, J = 7.8 Hz, 2H), 7.35 (d, J = 7.8 Hz, 4H), 7.21 (d, J = 7.8 Hz, 4H), 7.16 (d, J = 7.8 Hz, 4H), 6.09-6.02 (m, 2H), 5.45-5.40 (m, 2H, 2H), 5.33-5.29 (m, 2H), 4.86-4.82 (m, 4H), 2.73 (septet, J = 6.8 Hz, 3H), 1.18-1.16 (m, 24H). [ka]

[0117] To M2 (2.20 g, 2.30 mmol) in dichloromethane (28 ml) was added dropwise a solution of tribromoborane (1.31 ml, 13.8 mmol) in 5 ml of dichloromethane at 0° C., and the reaction mixture was stirred at 20° C. for 20 h. The reaction mixture was cooled in an ice bath and slowly hydrolyzed with methanol, followed by concentration. The crude product was dissolved in methanol, precipitated with water, and filtered. The paste thus obtained was dried overnight in a vacuum oven at 80° C. to give 2,9-bis(2,6-diisopropylphenyl)-5,12-bis(4-hydroxyphenoxy)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone as a purple solid (2.15 g, 93%). The crude product was used without any further purification. 1H NMR (400 MHz, acetone) δ 9.79 (d, J = 8.3 Hz, 2H), 8.70 (d, J = 8.3 Hz, 2H), 8.35 (s, 2H), 7.50-7.43 (m, 2H), 7.36 (d, J = 7.9 Hz, 4H), 7.26 (d, J = 8.7 Hz, 4H), 7.02 (d, J = 8.7 Hz, 4H), 2.82 (m, 4H), 1.18-1.11 (m, 24H).

[0118] To a solution of 2,9-bis(2,6-diisopropylphenyl)-5,12-bis(4-hydroxyphenoxy)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone (430 mg, 464 μmol) in acetonitrile (9.7 mL) was added potassium carbonate (513 mg, 3.71 mmol) and 3-bromoprop-1-ene (321 μL, 3.71 mmol), and the reaction mixture was stirred in a microwave oven at 100° C. for 6 h. The reaction mixture was concentrated, and the crude product was dissolved in dichloromethane and extracted three times with 1 M HCl. The combined organic phases were dried over magnesium sulfate, filtered, and concentrated to give 5,12-bis(4-(allyloxy)phenoxy)-2,9-bis(2,6-diisopropylphenyl)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone (M6) as a reddish-pink solid (400 mg, 86%). 1H NMR (400 MHz, CDCl3) δ 9.71 (d, J = 8.3 Hz, 2H), 8.73 (d, J = 8.3 Hz, 2H), 8.42 (s, 2H), 7.52-7.46 (m, 2H), 7.37-7.30 (m, 4H), 7.18-7.14 (m, 4H), 7.04-7.0 (m, 4H), 6.10 (ddt, J = 17.3, 10.5, 5.3 Hz, 2H), 5.46 (dq, J = 17.3, 1.6 Hz, 2H), 5.38-5.28 (m, 4H), 4.59 (dt, J = 5.3, 1.6 Hz, 4H), 2.83-2.66 (m, 4H), 1.25-1.10 (m, 24H). [ka]

[0119] To a solution of 2,9-bis(2,6-diisopropylphenyl)-5,12-bis(4-hydroxyphenoxy)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone (2.0 g, 2.16 mmol) in tetrahydrofuran (26 mL) was added triethylamine (1.80 mL, 12.9 mmol) and acryloyl chloride (1.05 mL, 12.9 mmol), and the reaction mixture was stirred at 20° C. for 60 minutes. The reaction mixture was then concentrated, suspended in water, and filtered. The crude product was dissolved in dichloromethane and extracted with 1 M NaOH. The combined organic phases were dried over magnesium sulfate, filtered, and concentrated. Purification by silica gel column chromatography (100% dichloromethane) gave ((2,9-bis(2,6-diisopropylphenyl)-1,3,8,10-tetraoxo-1,2,3,8,9,10-hexahydroanthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-5,12-diyl)bis(oxy))bis(4,1-phenylene)diacrylate (M7) as a red solid (2.20 g, 85%). 1H NMR (400 MHz, CDCl3) δ 9.64 (d, J = 8.3 Hz, 2H), 8.74 (d, J = 8.3 Hz, 2H), 8.48 (s, 2H), 7.54-7.46 (m, 2H), 7.39-7.30 (m, 4H), 7.26-7.20 (m, 8H), 6.64 (dd, J = 17.3, 1.3 Hz, 2H), 6.35 (dd, J = 17.3, 10.4 Hz, 2H), 6.06 (dd, J = 10.4, 1.3 Hz, 2H), 2.75 (septet, J = 6.3 Hz, 4H), 1.19-1.16 (m, 24H). [ka]

[0120] To a solution of M1 (535 mg, 616 μmol) in dimethylformamide (23.8 ml) was added K2CO3 (255 mg, 1.85 mmol) and 4-(2-hydroxyethyl)phenol (255 mg, 1.85 mmol), and the reaction mixture was stirred at 110°C for 2 h. The reaction mixture was cooled to room temperature and then poured into 2 M HCl. The pink precipitate was filtered, dissolved in dichloromethane, and extracted twice with 1 M NaOH. The combined organic phases were dried over magnesium sulfate, filtered, and concentrated to give 2,9-bis(2,6-diisopropylphenyl)-5,12-bis(4-(2-hydroxyethyl)phenoxy)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone as a pink solid (500 mg, 82%). 1H NMR (400 MHz, CDCl3) δ 9.65 (d, J = 8.3 Hz, 2H), 8.72 (d, J = 8.3 Hz, 2H), 8.45 (s, 2H), 7.51-7.47 (m, 2H), 7.39-7.29 (m, 8H), 7.20-7.12 (m, 4H), 3.93 (t, J = 6.4 Hz, 4H), 2.93 (t, J = 6.4 Hz, 4H), 2.74 (septet, J = 6.7 Hz, 1H), 1.19-1.15 (m, 24H).

[0121] To a solution of 2,9-bis(2,6-diisopropylphenyl)-5,12-bis(4-(2-hydroxyethyl)phenoxy)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone (570 mg, 580 μmol) in tetrahydrofuran (7 mL) was added triethylamine (342 μL, 2.45 mmol) and acryloyl chloride (241 μL, 2.98 mmol) diluted in 2 mL of tetrahydrofuran at 20° C. dropwise. The reaction mixture was stirred for 1 h. The reaction mixture was then concentrated, suspended in water, and filtered. The crude product was dissolved in dichloromethane and extracted three times with 1 M NaOH. The combined organic phases were dried over magnesium sulfate, filtered, and concentrated to give (((2,9-bis(2,6-diisopropylphenyl)-1,3,8,10-tetraoxo-1,2,3,8,9,10-hexahydroanthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-5,12-diyl)bis(oxy))bis(4,1-phenylene))bis(ethane-2,1-diyl)diacrylate (M8) as a dark pink solid (620 mg, 98% yield). 1H NMR (400 MHz, CDCl3) δ 9.66 (d, J = 8.3 Hz, 2H), 8.73 (d, J = 8.3 Hz, 2H), 8.45 (s, 2H), 7.49 (t, J=7.8 Hz, 2H), 7.37-7.33 (m, 8H), 7.17-7.14 (m, 4H), 6.41 (dd, J = 17.3, 1.4 Hz, 2H), 6.14 (dd, J = 17.3, 10.4 Hz, 2H), 5.84 (dd, J = 10.4, 1.4 Hz, 2H), 4.42 (t, J = 6.9 Hz, 4H), 3.04 (t, J = 6.7 Hz, 4H), 2.74 (m, J = 6.7 Hz, 3H), 1.19-1.15 (m, 24H). [ka]

[0122] To a solution of M1 (350 mg, 403 μmol) in dimethylformamide (3 mL) under argon, potassium carbonate (167 mg, 1.21 mmol) and 4-(2-hydroxyethoxy)phenol (186 mg, 1.21 mmol) were added, and the reaction mixture was stirred at 95° C. for 2 h. The reaction mixture was cooled to room temperature and then poured into 2 M HCl. The purple precipitate was filtered, dissolved in dichloromethane, and extracted twice with 1 M NaOH. The combined organic phases were dried over magnesium sulfate, filtered, and concentrated to give 2,9-bis(2,6-diisopropylphenyl)-5,12-bis(4-(2-hydroxyethoxy)phenoxy)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone as a purple-pink solid (318 mg, 78%). 1H NMR (400 MHz, CDCl3) δ 9.68 (d, J = 8.3 Hz, 2H), 8.72 (d, J = 8.3 Hz, 1H), 8.38 (s, 2H), 7.46 (t, J = 7.8 Hz, 2H), 7.31 (d, J = 7.8 Hz, 4H), 7.17-7.12 (m, 4H), 7.04-6.99 (m, 4H), 4.12 (m, 4H), 3.99 (m, 4H), 2.79-2.63 (m, 4H), 2.0 (t, J = 6.2 Hz, 2H), 1.21-1.09 (m, 24H).

[0123] To a solution of 2,9-bis(2,6-diisopropylphenyl)-5,12-bis(4-(2-hydroxyethoxy)phenoxy)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone (300 mg, 296 μmol) in tetrahydrofuran (3.6 ml), diluted triethylamine (179 mg, 1.77 mmol) and acryloyl chloride (160 mg, 1.77 mmol) were added dropwise at 20° C. The reaction mixture was stirred at 20° C. for 60 minutes. The reaction mixture was then concentrated, suspended in 2 M HCl, and filtered. The crude product was dissolved in dichloromethane and extracted three times with 1 M NaOH. The combined organic phases were dried over magnesium sulfate, filtered, and concentrated to give ((((2,9-bis(2,6-diisopropylphenyl)-1,3,8,10-tetraoxo-1,2,3,8,9,10-hexahydroanthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-5,12-diyl)bis(oxy))bis(4,1-phenylene))bis(oxy))bis(ethane-2,1-diyl)diacrylate (M9) as a dark pink solid (300 mg, 90% yield). 1H NMR (400 MHz, CDCl3) δ 9.67 (d, J = 8.3 Hz, 2H), 8.71 (d, J = 8.3 Hz, 2H), 8.38 (s, 2H), 7.51-7.43 (m, 2H), 7.32 (d, J = 7.8 Hz, 4H), 7.17-7.10 (m, 4H), 7.03-6.97 (m, 4H), 6.46 (dd, J = 17.3, 1.4 Hz, 2H), 6.17 (dd, J = 17.4, 10.4 Hz, 2H), 5.87 (dd, J = 10.4, 1.4 Hz, 2H), 4.58-4.50 (m, 4H), 4.28-4.21 (m, 4H), 2.71 (septet, J = 6.7 Hz, 6H), 1.23-1.09 (m, 24H).

[0124] Preparation of UV-curable security inkjet ink compositions

[0124] The viscosities of ink vehicles V1-V4 were determined using a Brookfield DV1 LV viscometer equipped with spindle LV1 at a rotation speed of 30 rpm and a temperature of 45°C.

[0125] The ink vehicle (V1, Table 1A) was prepared by adding each component sequentially to a brown polypropylene bottle and dispersing them using a Silverson L5M-A high-shear mixer equipped with a square-hole screen. After each addition, the mixture was dispersed at approximately 5000 rpm for approximately 5 minutes. Finally, the mixture was manually filtered using a 5 μm nylon syringe filter. [Table 2]

[0126] Ink vehicles (V2-V4, Table 1B) were prepared independently by adding each component sequentially to a brown polypropylene bottle and dispersing them using a Silverson L5M-A high-shear mixer equipped with a square-hole screen. After each addition, the mixture was dispersed at approximately 5000 rpm for approximately 5 minutes. Finally, the mixture was manually filtered using a 5 μm nylon syringe filter. [Table 3]

[0127] The security inks (Tables 2A and 2B) were prepared by adding the markers separately to the ink vehicle and placing the mixture in an ultrasonic bath for 20 minutes. The security inks were then allowed to stand at room temperature for 12 to 24 hours before use. [Table 4] [Table 5]

[0128] Fabrication of security features

[0128] The substrate used to create the security features is an unsealed black and white test chart, Leneta N2C-2, obtained from Leneta Company Inc. The white portion of the substrate is non-fluorescent white paper.

[0129]

[0129] Using a semi-automatic coater (RK print K Control Coater, Model 001) equipped with bar coating #1 (theoretical thickness approximately 6 μm), each of the UV-curable security ink compositions C1-C12 and E1-E6 was hand-printed onto the white portion of a Leneta N2C-2 substrate to form independent layers, thereby producing security features having rectangular shapes measuring 13 cm x 10 cm. The hand-printing method is used to mimic inkjet printing, particularly drop-on-demand (DOD) inkjet printing.

[0130] Next, a UV-LED light source (IST LUV20) was used, at 385 nm and a dose of 200 mJ / cm 2 The resulting layers were independently at least partially cured at .

[0131] The composition of Example E6 was applied to the white part of a Leneta N2C-2 substrate by a drop-on-demand inkjet printing process using a KM1024i inkjet head (Konica Minolta), and then irradiated with an IST LUV20 LED-UV lamp (385 nm, 200 mJ / cm). 2 ) was used to create security features in the form of QR codes measuring 1.5 cm x 1.5 cm (shown in Figure 1) by curing the printed composition.

[0132] Security Feature Characteristics Fluorescence intensity

[0132] The fluorescence intensity of the security features made from UV-cured compositions E1-E6 and comparative compositions C1-C12 was obtained by measuring the entire fluorescence spectrum emitted by the security features with a Fluorolog III instrument (Horiba Scientific) using the following parameters: R13456 Photomultiplier tube (PFR Technologies LLC) (185~950nm) Configuration: FL3-22 Angle: 30° Position: Front The excitation and detection slits were fixed for each series of measurements and are shown in Tables 3A-3B. Only measurements using the same excitation and detection slits can be directly compared.

[0133] The excitation wavelengths (shown in Tables 3A and 3B) correspond to the excitation maxima of each marker. To determine the excitation maxima, emission spectra were measured using excitation wavelengths close to the estimated maxima. The excitation spectrum was then recorded at the emission maxima wavelength, and the final emission spectrum was obtained by irradiating at the determined excitation maxima wavelength.

[0134]

[0134] The maximum fluorescence intensity was derived from the emission spectra and is shown in Tables 3A-3B as maximum absolute fluorescence intensity (photons / second). Relative values ​​(%) were also obtained by comparing the fluorescence intensity of compositions E1 (without colorant) and E4-E6 (with colorant).

[0135] Light fastness

[0135] The light fastness of security features made with the cured UV-curable security inkjet ink composition was determined by subjecting said security features to the Xenotest procedure (Norm ISO 105 B02). The measurement parameters were as follows: Equipment: Xenotest 220+ (Atlas MTT GmbH) Xenon lamp (2200W, 42W / m 2 ) Conditions: 35°C (test chamber), 48% (black BST panel), 40% relative humidity Ventilation device rotation speed: 2500 rpm Filter:<320nm

[0136] The security features were exposed to irradiation times of 3, 7, 24, 48, and 72 hours in a Xenotest device. After each step, the fluorescence spectrum was recorded, and the maximum fluorescence intensity was determined from the spectrum and compared to the maximum fluorescence intensity before aging. When the measured maximum fluorescence intensity decreased to less than 50% of its initial value, a light fastness value of 1 to 4 was assigned according to the following scale: [Table 6] [Table 7] [Table 8]

[0137]

[0137] As is evident from the data of the examples, the examples of the present invention exhibit a suitable and advantageous balance of properties in terms of fluorescence intensity, and more specifically, improved lightfastness even at low concentrations. The examples also provide the best printing performance, especially when incorporated into inkjet security ink compositions. The homogeneity of UV-curable ink compositions E1 to E6 is representative of the compatibility of the markers in pigmented or unpigmented UV-curable security ink compositions, especially in terms of solubility.

Claims

1. a) about 40 to about 95 wt %, preferably about 60 to 95 wt %, of one or more radically curable monomers, one or more oligomers, or a mixture thereof; b) from about 0.1 to about 20% by weight, preferably from about 1 to 15% by weight, of at least one free radical photoinitiator; c) about 0.005 to about 5% by weight, preferably about 0.01 to 1% by weight, of at least one compound P, (1) and (2) 【Chemistry 1】 (In the formula, (W) is preferably a rylene moiety (W) comprising any one of a perylene, terrylene, or quaterrylene core structure, and at least one aryl group of formula (3) bonded to the rylene moiety (W): 【Chemistry 2】 is a rylene moiety containing a substituent of R １ , R ２ , R ３ are independently carbocyclic or heterocyclic substituents, R １ and R ２ is bonded to the imide N of the rylene moiety (W), preferably directly, and in the case of compound (2), R ３ is directly attached to the naphthalene ring, --- is R ３ indicates the optional presence of substituents, Ar ４ is an aromatic substituent, Y is a linker, R' is either H or methyl. and a compound P having a structure selected from the group consisting of: d) optionally, from about 0.1 to about 2% by weight of at least one photosensitizer; e) optionally, from about 0.1 to about 20% by weight of at least one colorant; f) optionally, from about 0.01 to about 10% by weight of at least one additive, preferably from about 0.01 to about 1% by weight of at least one surfactant; 1. A UV curable security ink composition comprising:

2. 2. The UV curable security ink composition of claim 1, wherein the free radical photoinitiator is selected from the group consisting of aminoketone compounds, hydroxyketone compounds, alkoxyketone compounds, acetophenone compounds, benzophenone compounds, ketosulfone compounds, benzil ketal compounds, benzoin ether compounds, glyoxylate compounds, phosphine oxide compounds, and mixtures thereof, preferably selected from the group consisting of phosphine oxide compounds.

3. The UV-curable security ink composition according to claim 1 or 2, wherein the at least one photosensitizer is a thioxanthone compound.

4. 4. The UV curable security ink composition according to any one of claims 1 to 3, wherein the ink composition comprises about 0 wt% of the at least one colorant, and the at least one compound P is present in a total amount of about 0.005 wt% to about 0.2 wt%, the wt% being based on the total weight of the UV curable security ink composition.

5. 4. The UV curable security ink composition according to any one of claims 1 to 3, wherein the ink composition comprises from about 0.1 wt % to about 20 wt %, preferably from about 5 to about 10 wt %, of at least one colorant, and the at least one compound P is present in a total amount of from about 0.05 wt % to about 1.0 wt %, the wt % being based on the total weight of the UV curable security ink composition.

6. The UV curable security ink composition of claim 5 , wherein the at least one colorant is an IR-transparent pigment or an IR-transparent dye.

7. The linker Y is -(CH ２ ) ｊ -, -O-(CH ２ ) ｋ -, - [- (CH ２ ) ｌ -O] ｍ - (CH ２ ) ｐ wherein j=0 to 6, k=1 to 6, l=1 to 3, m=1 to 3, and p=1 to 3.

8. R １～３ The UV-curable security ink composition according to any one of claims 1 to 7, wherein the substituent is an aromatic substituent.

9. R １～３ The substituent has the structure (4): 【Transformation 3】 (In the formula, R ４ , R ５ , and R ６ are independently hydrogen, C １ ~C ４ Alkyl and its isomers, C １ ~C ４ Alkoxy, C １ ~C ４ The UV curable security ink composition of claim 8 , wherein the aryl group is an aminoalkyl, an aminoalkyl group, or a (fused) aromatic group.

10. R ３ The UV curable security ink composition according to any one of claims 1 to 7, wherein the substituent is a heterocyclic substituent, preferably an N-containing heterocyclic substituent.

11. 11. The UV-curable security ink composition according to any one of claims 1 to 10, which is an ink composition for screen printing having a viscosity of about 50 mPa·s to about 3000 mPa·s at 25°C, an ink composition for flexographic printing having a viscosity of about 50 mPa·s to about 2000 mPa·s at 25°C, an ink composition for rotogravure printing having a viscosity of about 50 mPa·s to about 1000 mPa·s at 25°C, or an ink composition for a non-contact fluid microdispensing process having a viscosity of about 1 mPa·s to about 1000 mPa·s at 25°C.

12. 12. The UV curable security ink composition according to claim 11, which is a non-contact fluid micro-dispensing process printing ink composition, preferably an ink jet printing ink composition, more preferably a drop-on-demand (DOD) ink jet printing ink composition having a viscosity of less than 30 mPa s at 25°C.

13. A security feature made of a cured layer of the security ink composition of any one of claims 1 to 12.

14. A security document or article comprising a security feature according to claim 13.

15. 14. A method of making a security feature according to claim 13, comprising the steps of: a) applying the UV curable security ink composition according to any one of claims 1 to 12 to a substrate, preferably by a printing process; b) at least partially curing the UV-curable security ink composition from step a), wherein the curing is preferably performed using a UV-LED light source, more preferably a UV-LED light source having a wavelength of about 360 nm to about 410 nm; A method comprising:

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