EP2203313B1 - Security film comprising an iridescent security mark - Google Patents

Description

The invention relates to a security sheet comprising a colored security mark and exhibiting an iridescent effect and to a document comprising said sheet.

To guard against counterfeiting or falsification of security documents such as means of payment such as banknotes, checks, or official documents, in particular identification documents such as passports, identity cards, or tickets. 'entry to cultural or sporting events or transport tickets or even packaging or labels comprising an authentication element, various security means can be used such as for example security threads, holograms, watermarks, or even pigments iridescent which allow a document to be authenticated by their interference effect which creates a change of colors observable from certain angles. In addition, these pigments protect against photocopying, the iridescent effect not being copiable.

In particular, the European patent application has described EP-A-0490825 a security paper comprising a surface application containing iridescent pigments which is practically not visible under direct observation (that is to say facing the plane of the surface of the application on the paper) which does not manifest its effect of coloration only when observed from an oblique viewing angle and which modifies its coloration upon modification of the viewing angle, said paper being characterized in that various surface areas, simultaneously perceptible, are provided with applications which contain different iridescent pigments and which present a different coloration on oblique observation. Preferably, these zones are contiguous bands. Such an effect allows an observer not to see the iridescent bands in direct observation but only in oblique observation, the fact of putting bands simultaneously perceptible allows a better relative perception of the color changes of each band in oblique observation. However, the fact that these bands are not visible in direct observation means that an uninformed observer such as "the man of the rue ”who wants to authenticate a document does not know where to locate these bands when he normally observes the document and / or forgets to do this check.

In the French patent application FR-A1-2855640 a security pattern has been described formed of a first pattern with substances with an interference effect and another pattern with substances reacting to certain stimuli giving a light response to the human eye, in particular fluorescent substances (reacting to rays UV). This securing means requires a device to stimulate the second pattern and make it visible.

Requirement FR 2 782 470 describes an iridescent ink deposited on a film applied to a support and colored when viewed by direct reflection.

Requirement EP 1 489 151 describes a security ink comprising an iridescent pigment exhibiting two different colors by observation in reflection.

The aim of the present invention is to solve the problems of the prior art and therefore to provide a security sheet with an authentication means which is easily observable by the man in the street while having a sufficient level of security.

The present invention provides a security means which is both visible under normal (front) observation with effects visible only from one or more other viewing angle (s) (obliquely) to the naked eye.

The invention thus has the advantage that the man in the street knows where to observe this means and, moreover, the visibility of certain effects only from certain angles gives it a high sufficient level of safety.

More precisely, the invention provides a security sheet comprising an iridescent security mark observable on the surface (of the sheet), which is characterized in that this said mark comprises at least one zone exhibiting an iridescent effect, said zone being colored in normal observation and with the naked eye and comprising almost colorless iridescent pigments in normal observation and presenting an iridescent effect visible only in oblique observation.

By "normal observation" is meant that an observer looks at the mark or the zone facing the plane respectively of the mark or the zone, that is to say at approximately 90 degrees relative to the plane respectively of said mark or of the zone, in white light (artificial or natural). This observation can also be qualified as a direct observation.

By "observable with the naked eye" is meant that no device is necessary to stimulate the coloring, a magnifying means, such as a magnifying glass, which can be used to be able to see the area as in the case where the area is formed of micro characters.

In the present invention, the iridescent effect of at least said zone is therefore practically invisible in normal observation (from the front) and visible only in oblique observation, that is to say only at angles other than at 90 degrees and, moreover, the iridescent pigments of this zone do not appear intrinsically colored under normal observation, they are intrinsically almost imperceptible under normal observation. The area is made noticeable under normal observation by the fact that it is colored, for example by the addition of a dye.

The invention provides a security sheet comprising an iridescent security mark observable on the surface which is characterized in that said mark comprises at least two zones each exhibiting an iridescent effect, said zones being colored in normal observation and with the eye. naked and at least one of the zones comprising (intrinsically) quasi-colorless iridescent pigments in normal observation and exhibiting an iridescent effect (change of colors) visible only in oblique observation.

Generally the zone or zones and the mark are flat and the zone or zones are in the same plane as that of the mark.

Preferably, the two said zones comprise iridescent pigments (intrinsically) quasi-colorless (imperceptible) in normal observation and exhibiting iridescent effects visible only in oblique observation.

Said zones are of a uniform color under normal observation and exhibit different iridescent effects under oblique observation. More particularly, said zones each comprise on the one hand a dye, said dye being such that said zones have the same shade, and on the other hand iridescent pigments, said pigments exhibiting different iridescent effects from one zone to another. .

According to a particular case of the invention, one of the zones may comprise iridescent pigments exhibiting a (non-iridescent) coloration under normal observation. In this case, the dye added to the iridescent compositions can have the same color as the pigments so as to mask the coloring of the pigments under normal observation.

According to another particular case not included in the invention, said zones are of different colors under normal observation and exhibit substantially identical iridescent effects under oblique observation. More particularly, said zones each comprise on the one hand a dye, said dye being such that the hue is different from one zone to another, and on the other hand iridescent pigments, said pigments exhibiting iridescent effects which are identical to one another. zone to another, preferably the iridescent pigments are identical in each zone.

Preferably, said dye is of a pastel shade. The amounts are adjusted according to the desired effect so that the iridescent effect is not masked. Those skilled in the art can adjust the amounts by measuring the colorimetric coordinates such as the CIELAB coordinates and the Gardner shine of the iridescent and colored compositions making it possible to produce the iridescent zones applied to the support to be protected. According to the invention, the amount of dye is between 0.05 and 0.2% relative to the iridescent pigments, by dry weight.

Preferably, the quantity of iridescent pigments deposited on said sheet is between 2 and 8 g / m ² .

The iridescent pigments can be chosen in particular from mica / titanium dioxide base pigments. They can be chosen from the Iriodin® ranges from Merck or Mearlin; Phoenix by Eckart, the products of Taïzhu, Longhua or Hang Zhou Riwa Chemical. They can also be chosen from the Dynacolor products from Engelhard; Chromaflair / Secureshift by Flex Product.

Preferably according to the invention, said zones can be observed simultaneously.

The zone (s) can be one or more continuous bands, which are solid or with recesses and / or a series of repeating or different patterns, which can be linked together and / or separate.

According to a particular embodiment of the invention, said zones are juxtaposed.

According to another particular embodiment of the invention, said zones are nested one inside the other.

According to a particular case of the invention, said zones are partially superimposed and thus form another colored and iridescent zone.

According to a particular case of the invention, said security mark, in particular the at least said zone, comprises a pattern, in negative or in positive, free from an iridescent effect.

According to a particular case of the invention, said security mark, in particular the at least said zone, further comprises a compound which can be observed under UV radiation.

More particularly, each of said zones comprises a fluorescent compound, said compound being different depending on the zone.

According to a particular case of the invention, said security mark further comprises at least one tactile effect element. This tactile effect can in particular be soft or rough.

Preferably, said tactile element is present at the level of at least said zone.

According to a first case, said element with a tactile effect is a polyurethane (PU), in particular chosen from PU microspheres and PUs in PU aqueous dispersion (“latex”), they can in particular confer a soft feel.

According to another particular case, said element with a tactile effect is composed of the iridescent pigments of the at least said zone, they can impart in especially a little rough to the touch, for example using somewhat coarse pigments.

According to a particular case of the invention, said tactile effect element comprises a first tactile effect originating from the PU present in one of the zones and a second tactile effect originating from iridescent pigments present in the other zone.

According to the invention, the security sheet is based on cellulose fibers, in particular cotton, and / or synthetic fibers such as polyamide and / or polyester fibers, or based on a plastic sheet such as a film polyolefin, for example extruded polyethylene. The basis weight of said sheet depends on the intended application, in particular it is between 80 and 150 g / m ² .

The security mark is applied to the support of the sheet, for example by gravure or by screen printing.

According to the invention, the sheet may further comprise another security element such as a watermark, a security thread, a hologram. According to a particular case, said iridescent security mark is free from another security element affixed to its surface, in particular from an optically variable element (called “OVD”).

The invention also relates to a security document comprising said sheet. According to the invention, the security document is chosen from identity documents, in particular an identity card or a passport, means of payment, in particular banknotes or checks, entrance tickets to cultural or sporting events, transport tickets, playing cards. The document can also be chosen from secure packaging, in particular for drugs, electronic parts, spare parts, perfumes and secure labels.

The invention will be better understood with the aid of the following examples according to the invention 2 to 5, 7 and 8 and of the figures 1 to 10 corresponding appended.

The figures 1, 3 and 5 show a front view of security sheets according to the invention in normal observation and the figures 2, 4 and 6 in oblique observation, as indicated in the description of the examples.

Example 1:

On a sheet of security paper, having a basis weight of 100 g / m ² , a security mark is printed by gravure printing in the form of a strip, while leaving a recess in the form of "10", by application of an aqueous ink. comprising a blue dye (Bleu Cartaréne CBR 500 from the company Clariant) and iridescent pigments based on mica / TiO2 (Iriodin® or 205 from the company Merck) exhibiting a gold iridescent effect, visible only in oblique observation. The ink can contain other customary additives such as crosslinking, antifoam, binders (water-soluble binder such as PVA and / or latex-type binders such as a polyurethane), or even viscosity regulator.

The ink comprises 44.8 g of iridescent pigments and 0.05 g of blue dye per 100 g of the ink composition by dry weight. The deposit by gravure printing of the iridescent composition is 12 g / m ² , the deposit of iridescent pigments being 5.4 g / m ² ; there is 0.11%, by dry weight, of dye deposited relative to the iridescent pigments.

This gives a mark appearing uniformly blue under normal observation (at an angle of 90 degrees to the plane of the region) with the pattern "10" appearing in negative (free of inks) and with a gold iridescent effect, appearing only. in oblique observation.

Example 2:

On a sheet of security paper 1, having a basis weight of 100 g / m ² , a security mark ² is printed by gravure printing by making a first zone 2a in the form of a strip, while leaving a recess in the form of "1". , by application of an A1 aqueous ink comprising a green dye (Cartarene CVB green from the company Clariant) and iridescent pigments based on mica / TiO ₂ (Iriodin® Bleu 225 from the company Merck) exhibiting a blue iridescent effect visible only in oblique observation and also making a second zone 2b in the form of a strip, juxtaposed to the first, while leaving two recesses side by side in the form of “0” and next to the “1” of zone 2a, by application of an aqueous ink B1 comprising said green dye and iridescent pigments based on mica / TiO ₂ (Iriodin® Lilac 219 from the company Merck) exhibiting a violet iridescent effect visible only when viewed obliquely. The iridescent pigments themselves are almost colorless under normal observation. The inks can contain other usual additives such as crosslinking, antifoam, binders (water-soluble binder such as PVA and / or latex-type binders such as a polyurethane), viscosity regulator. Each of the A1 and B1 inks comprises 44.8 g of iridescent pigments and 0.03 g of green dye per 100 g of the ink composition by dry weight. The tint of the inks was adjusted by colorimetric measurements and by Gardner gloss measurements. The deposit by gravure printing of the iridescent compositions A1 and B1 is 12 g / m ² (per composition) on the sheet, the deposit in iridescent pigments is 5.4 g / m ² and that in dye is 0.005 g / m ² ; there is therefore approximately 0.1%, by dry weight, of dye deposited relative to the iridescent pigments.

The colorimetric data for the brand made of the two bands is as follows: Gardner gloss at 75 degrees 28.5 CIE whiteness 40.8 ISO whiteness 70.4 Yellow degree 10.79 L 91.34 at* -5.87 b * 8.06

A mark is thus obtained composed of two juxtaposed zones (2a, 2b), said mark appearing uniformly green in normal observation (at an angle of 90 degrees with respect to the plane of the region) with the pattern "100" appearing in negative (free). of inks) as indicated on the figure 1 and with iridescent effects appearing only in oblique observation and different from one area to another as indicated on the figure 2 , zone 2a has a blue effect and zone 2b has a purple effect.

Example 3:

On a sheet of security paper 1, a security mark 2 is printed by screen printing by making a first zone 2a in the form of a strip by applying an aqueous ink A2 comprising a red dye and iridescent pigments based on mica / TiO _2. (Iriodin® 235 from the company Merck) exhibiting a green iridescent effect visible only in oblique observation and a second zone 2b nested in the first is also produced, in the form of a hexagon comprising two recesses in the form of “A” and “W”. "By applying an aqueous ink B2 comprising said red dye and iridescent pigments based on mica / TiO ₂ (Iriodin® 205 from the company Merck) exhibiting a gold iridescent effect visible only in oblique observation. The iridescent pigments themselves are almost colorless under normal observation. As in Example 2, the inks A2 and B2 have the same shade, this shade is adjusted according to each ink as a function of the other ingredients and in particular of the iridescent pigments. The inks can contain other usual additives such as crosslinking agent, antifoam, binders (water-soluble binder such as PVA and / or latex-type binders such as polyurethane), viscosity regulator and glycerin. Each of the A2 and B2 inks comprises 28.4 g of iridescent pigments and 0.03 g of red dye per 100 g of the ink composition by dry weight. The tint of the inks was adjusted by colorimetric measurements and by Gardner gloss measurements. The deposit by screen printing of the iridescent compositions A2 and B2 is 12 g / m ² (per composition), the deposit in iridescent pigments being 3.45 g / m ² and that in dyeing 0.0031 g / m ² , there is therefore has about 0.091%, by dry weight, of deposited dye relative to the iridescent pigments.

A mark is thus obtained composed of two overlapping zones (2a, 2b), said mark appearing uniformly red in normal observation with the pattern "AW" appearing in negative as indicated on the figure. figure 3 and with iridescent effects visible only in oblique observation and different according to the zones as indicated on the figure 4 showing the hexagon of zone 2b in band 2a.

Example 4:

The inks of Example 2 are used, to which a fluorescent compound is added to each of the inks; to ink A1 a red fluorescent compound is added, to ink B1 a blue fluorescent compound is added. As in Example 2, a security mark is made on a sheet. The mark appears red in zone 2a and blue in zone 2b under UV illumination.

Example 5:

The inks of Example 3 are used, to which a fluorescent compound is added to each of the inks; to ink A2 a red fluorescent compound is added, to ink B2 a blue fluorescent compound is added. As in Example 3, a security mark is made on a sheet. The mark appears red in zone 2a and blue in zone 2b under UV illumination.

Example 6:

On a sheet of security paper 1, a security mark 2 is printed by gravure printing by making a first zone 2a in the form of a strip by applying an A5 ink comprising a green dye and iridescent pigments based on mica / TiO ₂ ( Iriodin® 205 from the company Merck) exhibiting a gold iridescent effect, visible only in oblique observation, and a second zone 2b juxtaposed to the first is also produced, in the form of a hexagon comprising two recesses in the form of “A” and “W »By applying a B5 ink comprising a blue dye and the same iridescent pigments as for the A5 ink. The iridescent pigments themselves are almost colorless under normal observation. A5 and B5 inks therefore have a different shade.

A mark is thus obtained composed of two overlapping zones, said region appearing in the form of two zones of different shades in normal observation, one green and the other blue in the form of a hexagon with the pattern "AW" appearing in negative as indicated on the figure 5 and with iridescent effects visible only in oblique observation and similar in the two zones, the hexagon no longer standing out as indicated on the figure 6 .

Example 7:

On a sheet of security paper 1, a security mark 2 is printed by gravure printing in the form of a strip, by producing a first zone 2a in the form of a strip comprising recesses in the form of "100" and recesses in the form of "AW", by application of an ink comprising a green dye (Catarene green from the company Clariant) and iridescent pigments based on mica / TiO ₂ (Iriodin® Lilac 219 from the company Merck) exhibiting a violet effect visible only on observation oblique. A second zone 2b is also produced in the form of a "100" pattern by applying an ink comprising the same green dye (Catarene green from the company Clariant) and iridescent pigments based on mica / TiO ₂ (Iriodin® 225 from the company Merck) exhibiting a blue effect visible only in oblique observation, said "100" patterns being applied to the mark with respect to the "100" shaped recesses of the first zone 2a, so as to coincide. The iridescent pigments of zones 2a and 2b are almost colorless under normal observation.

In this way, under normal observation, a mark appearing as a green band with "100" recesses is obtained, as indicated in figure 7 . In oblique observation, a band is obtained having a violet effect, with recesses (free of ink) in the shape of "AW" and "100" patterns exhibiting a blue effect, as indicated in figure 8 .

Example 8:

On a sheet of security paper 1, a security region 2 is printed by gravure printing in the form of a strip, making a first zone 2a in the form of a strip comprising recesses in the form of a hexagon, by application of an ink comprising a green dye (Catarene green from the company Clariant) and iridescent pigments based on mica / TiO ₂ (Iriodin® Lilac 219 from the company Merck) exhibiting a violet effect visible only when viewed obliquely. A second zone 2b is also produced, by applying within each hexagon-shaped recess an "AW" pattern in an ink comprising a green dye (Catarene green from the company Clariant) and iridescent pigments based on mica / TiO _2. (Iriodin® 225 from the company Merck) exhibiting a visible blue effect only in oblique observation. The iridescent pigments of zones 2a and 2b are almost colorless under normal observation.

This gives, under normal observation, a mark appearing as a green band with recesses (ink-free) in the shape of a hexagon, each hexagon comprising an "AW" pattern of the same color as the band, as indicated in figure 9 . In oblique observation, a band is obtained having a violet effect, with recesses (free of ink) in the shape of a hexagon and "AW" patterns exhibiting a blue effect, as indicated in figure 10 .

Claims (11)

1. A security sheet (1) including an iridescent security mark (2) observable on the surface of the sheet (1), characterized by the fact that said mark includes at least two zones (2a, 2b), each presenting an iridescent effect, said zones being colored in normal observation with the naked eye and at least one of said zones including iridescent pigments that are practically colorless in normal observation and that present an iridescent effect that is visible only in oblique observation, each of said zones (2a, 2b) including firstly a dye, said dye being such that said zones have the same hue, and secondly iridescent pigments, said pigments presenting in oblique observation iridescent effects that differ from one zone to the other.
2. A security sheet according to claim 1, characterized by the fact that said two zones (2a, 2b) present iridescent effects that are visible only in oblique observation.
3. A security sheet according to claim 2, characterized by the fact that said two zones (2a, 2b) include iridescent pigments that are practically colorless in normal observation and that present iridescent effects that are visible only in oblique observation.
4. A security sheet according to any of the preceding claims, characterized by the fact that said zones (2a, 2b) are juxtaposed.
5. A security sheet according to one of claims 1 to 4, characterized by the fact that said zones are one within the other.
6. A security sheet according to one of claims 1 to 5, characterized by the fact that said zones (2a, 2b) are partially superposed.
7. A security sheet according to one of claims 1 to 6, characterized by the fact that each of said zones (2a, 2b) includes a fluorescent compound, said compound differing from one zone to the other.
8. A security sheet according to one of claims 1 to 7, characterized by the fact that said at least one mark (2) further includes at least one tactile-effect element, said tactile-effect element being present in said at least one zone (2a, 2b).
9. A security sheet according to claim 8, characterized by the fact that said tactile-effect element is a polyurethane, in particular selected from microspheres of polyurethane and polyurethanes used in an aqueous dispersion or characterized by the fact that said tactile-effect element is constituted by the iridescent pigments of said at least one zone (2a, 2b).
10. A security sheet according to one of claims 8 and 9, characterized by the fact that said at least one tactile-effect element comprising a polyurethane first tactile effect present in one of the zones (2a, 2b) and an iridescent-pigment second tactile effect present in the other zone.
11. A security document including a sheet (1) as described in any of the preceding claims and notably selected from identity documents, in particular an identity card or a passport, payment means, in particular bank notes or checks, tickets for entry to cultural or sports events, transport tickets, playing cards, secure packaging, in particular for medicines, electronic components, spare parts, perfumes, and secure labels.

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