Staining kit for staining valuables, apparatus and method

Description

FIELD OF THE INVENTION

[0001] The invention relates to a staining kit for staining valuables, in particular banknote paper, and an apparatus and method for staining valuables.

BACKGROUND OF THE INVENTION

[0002] Criminal deterring systems using substances to be sprayed on persons and/or material prone to theft have been known for a number of years. These systems include irritating and foul smelling substances admixed with dyes such as those described in US5405599, which both deter criminals and enable identification.

[0003] Dye systems are also known, for instance known from US 5,196,828. US 5,156,272 shows a banknote transport case having a dye system spilling dye on banknotes after an unauthorized breach of the case, leaving the banknotes useless.

[0004] WO2008/072193 shows a more advanced dye/pigment-based system, using dyes/pigments combined with a resin system, making it more difficult to remove the dyes/pigments from banknotes afterwards. This system uses methacrylates as the resin binder combined with a number of commercially available dyes/pigments.

[0005] It is the knowledge of the inventors that known dye/pigment-based systems generally suffer from the lack of permanency, i.e. lack of resistance to removal by use of chemicals such as organic solvents, bleaches and detergents, particular when attempts of removal are made by those skilled in the art of colour and polymer chemistry. The binding between pigments and banknotes, created via the use of polymer binders, often fail when exposed to carefully chosen solvents, resulting in the removal of both the pigments and the polymer binders without causing visible damage to the banknotes. In particular, not all dyes are satisfactory for neutralizing banknotes, as some dyes do not bind well to banknotes, in particular for banknotes that have an anti-fouling coating.

OBJECT AND SUMMARY OF THE INVENTION

[0006] It is an object of the invention to provide an improved banknote neutralization system. The invention provides a staining kit for staining valuables, in particular banknote paper, comprising; at least one adhesive composition, comprising polymerizable adhesive monomers capable of forming a polymer adhesive upon activation; at least one colorant composition, comprising at least one colorant, capable of yielding an adhesive-bound colorant with the adhesive composition; and at least one adhesive crosslinker, capable of activating the adhesive monomers when contacted with the adhesive composition. When brought into contact with the adhesive composition, the adhesive crosslinker accellerates the polymerization reaction, thus allowing for rapid formation of the polymer adhesive on the valuables to be stained. Before use, at least the adhesive composition and the adhesive crosslinker should be kept separated. The colorant composition is usually also kept separated from the adhesive composition, as during storage unwanted reactions may occur. When triggered, for instance in case of burglary or an alarm signal, all components of the kit are to be applied essentially simultaneously on the valuables to be stained. Upon mixing the adhesive formulation with the colorant composition and the adhesive crosslinker, rapidly an adhesive-bound colorant is formed on the valuables. Preferably, the adhesive composition and/or the colorant composition are liquid compositions. Appropriate solvents may be added in order to fully dissolve the ingredients.

[0007] Preferably, the at least one adhesive crosslinker is comprised in the colorant composition. Thus, the staining kit would only need two separate compositions, allowing for a more compact storage and easier simultaneous application to the valuables to be stained.

[0008] In a preferred embodiment, the at least one adhesive crosslinker comprises an alcohol, acid or ether. Alcohols, acids and/or ethers function well as an crosslinker and accellerator for the polymerization reaction of the adhesive. These are particularly suitable for activating cyanoacrylate polymerization. It is advantageous if the crosslinker is liquid at ambient temperature (20 °C), and is essentially non-volatile, typically having a vapor pressure below 20 kPa at 20 °C and a boiling point higher than water (100 °C at 1 atm). Epoxides are preferred as adhesive crosslinkers. Other suitable crosslinkers include ethanol, propanol, propionic acid, and acetic acid.

[0009] A particularly suitable adhesive crosslinker comprises glycerol propoxylate triglycidyl ether. This compound is essentially non-volatile, having a boiling point of 149 °C, dissolves in most solvents, and readily starts up polymerization when contacted with adhesive monomers, in particular cyanoacrylates. Alternative suitable crosslinkers include poly(ethylene glycol) diglycidyl ether, and Tris(2,3-epoxypropyl) isocyanurate.

[0010] It is preferred if at least the colorant composition is a liquid composition using a C1-4 lower alkyl alcohol as a solvent, preferably ethanol. Lower alkyl alcohols have proven to be very efficient in rapidly spreading the colorant composition over valuables, in particular various types of banknote paper.

[0011] Preferably, the adhesive monomers are selected from the group consisting of urethanes, epoxides and cyanoacrylates. These types of polymerizable adhesives have proven to be very efficient in binding colorants to valuables, in particular to banknotes. It is also possible to use a mixture of different monomers, yielding copolymers of urethanes, epoxides and/or cyanoacrylates.

[0012] Most preferably, the polymerizable adhesive comprises cyanoacrylate polymerizable monomers. Cyanoacrylates have proven to bind colorants rapidly to valuables, in particular banknote paper, and are difficult to remove. Another advantage is that cyanoacrylate has a relatively low toxicity for humans. Examples of suitable commercially available cyanoacrylate monomers are methyl 2-cyanoacrylate, ethyl 2-cyanoacrylate, n-propyl 2-cyanoacrylate, isopropyl 2-cyanoacrylate, tert-butyl 2-cyanoacrylate, n-butyl 2-cyanoacrylate, isobutyl 2-cyanoacrylate, 3-methoxybutyl cyanoacrylate, n-decyl cyanoacrylate, hexyl 2-cyanoacrylate, 2-ethoxyethyl 2-cyanoacrylate, 2-methoxyethyl 2-cyanoacrylate, 2-octyl 2-cyanoacrylate, 2-propoxyethyl 2-cyanoacrylate, n-octyl 2-cyanoacrylate, and isoamyl cyanoacrylate. These compounds may be used as pure monomers, or as mixed monomers to yield cyanoacrylate copolymers after polymerization.

[0013] Whilst performing well in terms of permanence of bonding, cyanoacrylate-based adhesives may suffer from lack of resistance to organic solvents such as acetone, which is an intrinsic solvent for most cross-linked cyanoacrylate based systems. Other problems associated with the cyanoacrylate-based systems are the relatively slow diffusion of the adhesive through paper-based banknotes, particularly those carrying a protective varnish layer.

[0014] In a preferred embodiment, the adhesive monomer comprises a C1-C4 alkyl cyanoacrylate. These monomers selected from the group consisting of methyl 2-cyanoacrylate, ethyl 2-cyanoacrylate, n-propyl 2-cyanoacrylate, isopropyl 2-cyanoacrylate, tert-butyl 2-cyanoacrylate, n-butyl 2-cyanoacrylate and isobutyl 2-cyanoacrylate show a faster spreading over the surface and into porous materials, in particular various types of banknote paper.

[0015] It is preferred if the colorant comprises a disperse dye and/or a cationic dye. Disperse dyes and cationic dyes enable intense staining of valuables. It is preferred if a mix of different types of dyes is used, as this makes it more difficult to remove the stain from the valuables. Most preferably, the colorant comprises a disperse dye and/or a cationic dye, combined with at least one dye coupling agent. Dye coupling agents react with the dyes to form a plethora of chemically modified dyes with different colour and binding properties, making it even harder to remove the dyes.

[0016] Preferably, the colorant comprises a disperse dye selected from the group consisting of Serilene Black SG Grains, Serilene Black T-LS 200, Serilene Brown 2B-LSN, Serilene B. Blue K-BGF, and Serilene Scarlet G-LS150, as supplied by Yorkshire Group. These dyes have shown excellent staining results.

[0017] Preferably, the colorant comprises at least one cationic dye selected from the group consisting of Brilliant Green, Brilliant Blue RL, and Dark Brown X-3RL, as supplied by Zhejiang Runtu Ltd. These cationic dyes have shown excellent staining results.

[0018] It is preferred if the cationic dye is admixed with an acid. Adding an acid provides a better binding of the cationic dye to certain types of valuables, in particular porous types of banknote paper.

[0019] It is preferred if the dye coupling agent compound is selected from the group consisting of phenols, disubstituted phenylenediamines and phenyleneaminophenols, and resorcinol derivatives. Preferred dye coupling agents are 1,3-phenylenediamine (m-phenylenediamine), 1,4-phenyldiamine (p-phenyldiamine), resorcin, 4-chlororesorcin, 1-naphtol, 3-aminophenol and 5-amino-2-methylphenol. Disubstituted phenyldiamines, in particular 1,3-phenylenediamine, 1,4-phenyldiamine are most preferred for use in bank note staining systems. The dye coupling agents, and in particular the phenylenediamines, react with sodium bromate to form pigments inside the paper fibre matrix giving permanent staining. When attempts are made to bleach the pigment formed, the cationic dye present is actually made darker. When attempts are made to remove the adhesive with organic solvent, the pigment formed and the dye contained in the adhesive will stain the whole banknote making the removal of the stain even harder. Thus, the bank note staining system according to the invention is much harder to overcome than known bank note staining systems.

[0020] The invention further provides an apparatus for staining valuables, in particular bank notes, using a kit according to the invention, wherein the apparatus comprises at least one first compartment comprising a colorant composition, at least one second compartment comprising an adhesive composition, and trigger means for applying the adhesive composition and the colorant composition from the first and second compartments as a mix onto valuables to be stained upon receiving a trigger signal. Such an apparatus may be integrated in for instance a cash dispenser machine, a money transport and/or storage container or vehicle.

[0021] The inventions also provides a method for staining valuables, in particular bank notes, using a kit according to the invention, comprising the steps of providing valuables, preferably bank notes; providing at least one adhesive composition, comprising reactive adhesive monomers capable of forming a polymer adhesive upon activation; providing at least one colorant composition, comprising at least one colorant, capable of forming yield an adhesive-bound colorant with the adhesive composition; providing at least one adhesive crosslinker, separated from the adhesive composition, for activating the adhesive monomers when contacted with the adhesive composition; wherein upon a trigger signal, the adhesive composition, the colorant composition and the adhesive crosslinker are applied to the valuables to be stained, forming an adhesive bound colorant on the valuables.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0022] The invention will now be further elucidated by the following non-limitative examples.

Examples

[0023] The examples show two different dye compositions, used as a first pack which may be combined with a second pack comprising an adhesive to form a banknote neutralisation system. The compositions shown in the examples are particularly suitable for use with a cyanoacrylate adhesive for permanently staining banknotes.

[0024] These dye compositions may be applied in for instance cash dispenser machines or cash transport containers, having at least one first compartment for the dye composition, at least one second compartment for the adhesive composition, and a triggered mechanism designed to apply the adhesive and dye as a mix onto the banknotes to be neutralized upon receiving a trigger signal. When the contents of the two compartments are mixed, a coloured resin or glue will be formed that upon contact will spoil the money stored in the cassette. This is used as a security measure. The trigger mechanism may for instance be a remote control or an automated alarm. Examples of suitable mechanisms are for instance described in EP 1 298 276 and US 5 598 793, that are incorporated herein by reference.

Example I

[0025] Quantities are shown as percentage by weight.

Table I: Dye Composition I

Material	Quantity (% w/w)
Serilene Black SG Grains	0.98
Brilliant Green [CAS: 633-03-4]	0.79
1-methyl-2-pyrrolidinone [CAS: 872-50-4]	49
Glycerol propoxylate triglycidyl ether [CAS: 37237-76-6]	6.55
Ethanol	42.48
Hydrochloric acid (37%)	0.20

Procedure of preparation

[0026] 0.3g Serilene Black SG Grains was dissolved in 15g of 1-methyl-2-pyrrolidone at 50°C. 0.06g of hydrochloric acid (37%) was added and the mixture was cooled down to ambient temperature. 0.24g of Brilliant Green to Mixture 2 was added and dissolved under stirring. 13g of ethanol was added and mixed to obtain a homogeneous mixture. Subsequently, 2g of glycerol propoxylate triglycidyl ether was added and mixed under stirring to yield the dye solution for a banknote neutralization system having a dark green colour. It is another advantage that the solution has a flash point of about 91 °C. Flash points above 60 °C are believed to be safe for the envisaged purpose, although a flash point above 100 °C is preferred.

[0027] Serilene Black SG and Brilliant Green act as staining dyes. 1-methyl-2-pyrrolidinone is a solvent for the dispersed dyes. Glycerol propoxylate triglycidyl ether is the crosslinker for crosslinking the dyes with the adhesive. Ethanol is a solvent for cationic dye. Hydrochloric acid (37%) acts as a colour enhancer for cationic dye.

Use for staining banknotes

[0028] When the dye composition according to example I was mixed with a cyanoacrylate adhesive and applied to a banknote, a dark green staining of the banknotes was obtained. Glycerol propoxylate triglycidyl ether acts as an crosslinker for the polymerization of the cyanoacrylate adhesive. The results is an adhesive-bound dye mixture which could not be removed by regular techniques such as organic solvents, bleaching agents or UV light without severely and vissibly damaging the banknote. Other adhesives may be used instead of cyanoacrylate. The dye composition combined with a suitable adhesive composition yields a very effective banknote neutralisation system.

[0029] A test was performed using the following procedure:

• application of the dye composition according to the invention in Table I to a bank note; the bank note was dipped into the dye solution for at least 5 seconds in order to achieve an adequate level of penetration.
• Application of an adhesive: de coloured bank note was dipped into an adhesive solution, in this case a cyanoacrylate solution.
• the bank note was dried for 30 seconds.

[0030] Subsequently, coloured pieces of the banknote were subjected to various solvents in order to assess the solvent resistance. A qualitative analysis is found in table II, with the following qualifications:

+++: great, virtually no difference compared to the untreated control

++ very good, lighter but still dark colouring

+ good, a lighter but still clearly visible with the bare eye

+/- barely visble colouring

- very difficult to spot with the bare eye

Table II: Solvent resistance of dye composition I.

Solvent	Test result	Solvent	Test Result
Ethoxypropanol	+++	DMF	+
1,2-dichlorobenzene	++	THF	+
Isolbutylmehthylketone	+++	N-methylpyrollidone	+++
Cyclohexanone	++	Toluene	+++
Methanol	+++	Dimethyl sulfoxide	++
Ethanol	++	Sodium hypochlorde	+++
2-methoxyethanol	++	Dipropylene glycol monomethylether	++
Acetone	+	hexane	+++
Ethyl acetate	++

[0031] From the table it becomes clear that the solution according to the invention offers excellent resistance to various organic solvents, as well as the oxidative sodium hypochlorite solution. Colour retention in all solvents was well above 1 (ΔE>>1).

Example 2

[0032] Quantities are shown as percentage by weight.

Table III: Dye Composition 2

Material	Quantity (% w/w)
Brilliant Green [CAS: 633-03-4]	2.5
1,3-phenylenediamine [CAS: 108-45-2]	7.5
1,4-phenylenediamine [CAS: 106-50-3]	(7.5)
Sodium bromate [CAS: 7789-38-0]	0.8
Propionic acid [CAS: 79-09-4]	87.2
Water	2%

Procedure of preparation

[0033] 1,3-phenylene diamine (or alternatively 1,4 -phenylene diamine), sodium bromate and half of the propionic acid were mixed under stirring and heating at 65°C for 60 minutes. The mixture was cooled to ambient temperature and subsequently, Brilliant Green was added. The mixture was stirred until complete dissolution of Brilliant Green, followed by addition of the remaining propionic acid and water while stirring. The mixture was filtered to obtain the dye formulation as the filtrate.

[0034] In this composition, Brilliant Green is the staining dye. M-phenylenediamine and p-phenylenediamine are precursors of the pigment. Propionic acid acts as a solvent/solubiliser for the phenylenediamines. Sodium bromate is an oxidant for pigment formation, oxidizing the phenylene diamines into reactive species. Water is the preferred solvent for the cationic dye.

Use for staining banknotes

[0035] When the dye composition according to example II was mixed with a cyanoacrylate adhesive and applied to a banknote, a dark green staining of the banknotes was obtained, which could not be removed by techniques such as organic solvents, bleaching agents or UV light without severely damaging the banknote. Other adhesives may be used instead of cyanoacrylates, although cyanoacrylates yield the fastest crosslinking reaction and are therefore preferred. The dye composition combined with a suitable adhesive composition yields a very effective banknote neutralisation system. Dye composition 2 was tested using the same method as described for composition 1. The results are shown in Table IV.

Table IV: Solvent resistance for composition 2.

Solvent	Test result	Solvent	Test Result
Ethoxypropanol	+++	DMF	+
1,2-dichlorobenzene	++	THF	+++
Isolbutylmehthylketone	++	N-methylpyrollidone	+++
Cyclohexanone	++	Toluene	+++
Methanol	++	Dimethyl sulfoxide	+++
Ethanol	++	Sodium hypochlorde	+++
2-methoxyethanol	++	Dipropylene glycol monomethylether	+++
Acetone	+	hexane	+++
Ethyl acetate	+++

[0036] Composition 2 showed a solvent resitance that was at least similar and for some solvents better than composition I. Both sytems I and II are however very suitable for bank note staining systems. The better resistance is believed to be due to a faster crosslinking reaction with the bank note material observed for composition 2, which is believed to be due to the presence of the diamines. With some of the solvents, in particular acetone, ethyl acetate, isobutyl methyl ketone, THF, methoxyethanol, ethoxypropanol and toluene, the colour is actually spread more through the bank note material rather than being washed out, actually achieving a more wide-spread colouring than after the initial staining. Interestingly, oxidative solutions, in this case bleach, changed the colouring to a deep black. The compostion also showed a strong resistance to caustic soda, changing the colour to a dark brown.

Claims

1. Staining kit for staining valuables, in particular banknote paper, comprising;

- at least one adhesive composition, comprising polymerizable adhesive monomers capable of forming a polymer adhesive upon activation;

- at least one colorant composition, comprising at least one colorant, capable of chemical bonding with the adhesive monomers; and

- at least one adhesive crosslinker, capable of activating the adhesive monomers when contacted with the adhesive composition.

2. Staining kit according to claim 1, wherein the at least one adhesive crosslinker is comprised in the colorant composition.

3. Staining kit according to claim 1 or 2, wherein the at least one adhesive crosslinker comprises an alcohol, acid or ether.

4. Staining kit according to claim 3, wherein the adhesive crosslinker comprises glycerol propoxylate triglycidyl ether.

5. Staining kit according to any of the preceding claims, wherein at least the colorant composition is a liquid composition using a C1-4 lower alkyl alcohol as a solvent, preferably ethanol.

6. Staining kit according to any of the preceding claims, wherein the adhesive monomers are selected from the group consisting of urethanes, epoxides and cyanoacrylates.

7. Staining kit according to claim 6, wherein the adhesive comprises at least one cyanoacrylate.

8. Staining kit according to claim 7, wherein the adhesive monomer comprises a C1-C4 alkyl cyanoacrylate.

9. Staining kit according to any of the preceding claims, wherein the colorant comprises a disperse dye and/or a cationic dye.

10. Staining kit according to claim 9, wherein the colorant comprises a disperse dye selected from the group consisting of Serilene Black SG Grains, Serilene Black T-LS 200, Serilene Brown 2B-LSN, Serilene B. Blue K-BGF, and Serilene Scarlet G-LS150.

11. Staining kit according to claim 9, wherein the colorant comprises at least one cationic dye selected from the group consisting of Brilliant Green, Brilliant Blue RL, and Dark Brown X-3RL.

12. Staining kit according to any of the preceding claims, wherein the dye coupling agent compound is selected from the group consisting of 1,3-phenylenediamine, 1,4-phenyldiamine, resorcin, 4-chlororesorcin, 1-naphtol, 3-aminophenol and 5-amino-2-methylphenol.

13. Staining kit according to claim 12, wherein the dye coupling agent comprises 1,3-phenylenediamine or 1,4-phenylenediamine, or a mixture thereof.

14. Apparatus for staining valuables, in particular bank notes, using a kit according to any of the preceding claims 1-13, wherein the apparatus comprises;

- at least one first compartment comprising a colorant composition;

- at least one second compartment comprising an adhesive composition; and

- trigger means for applying the adhesive composition and the colorant composition from the first and second compartments as a mix onto valuables to be stained upon receiving a trigger signal.

15. Method for staining valuables, in particular bank notes, using a kit according to any of the claims 1-13, comprising the steps of

- providing valuables, preferably bank notes,

- providing at least one adhesive composition, comprising reactive adhesive monomers capable of forming a polymer adhesive upon activation, and

- providing at least one colorant composition, comprising at least one colorant, capable of chemical bonding with the adhesive composition,

- providing at least one adhesive crosslinker, separated from the adhesive composition, for activating the adhesive monomers when contacted with the adhesive composition, wherein upon a trigger signal, the adhesive composition, the colorant composition and the adhesive crosslinker are applied to the valuables to be stained, forming an adhesive bound colorant on the valuables.