HK1174877B

HK1174877B - Chiral liquid crystal polymer marking

Info

Publication number: HK1174877B
Application number: HK13101987.8A
Authority: HK
Inventors: T．蒂勒; F．格里莫德; A．卡利加里
Original assignee: Sicpa Holding Sa
Priority date: 2009-12-08
Filing date: 2010-05-19
Publication date: 2015-09-11

Description

Chiral liquid crystal polymer marking

Cross reference to related applications

This application claims the benefit of U.S. provisional application No. 61/267,668, filed on even 12/8/2009, 35u.s.c. 119(e), the entire disclosure of which is expressly incorporated herein by reference.

Background

[ technical field of the invention ]

The invention relates to a marking based on chiral nematic (also called cholesteric) liquid crystal polymers. The invention also relates to a method for modifying a chiral nematic liquid crystal film, wherein the chiral nematic liquid crystal layer is modified locally or selectively (one or more regions) by a modifying agent.

[ Prior Art ]

Counterfeiting and market diversion of mass-produced goods would be facilitated if the products were processed on a bulk basis rather than on an individual item basis. In this case, counterfeit or diverted products are easily introduced into the supply chain. Both manufacturers and retailers desire to be in the position to distinguish their original products from such counterfeit or diverted (parallel input or smuggled) products at the individual unit level sold.

In an attempt to prevent counterfeiting, markers are now widely used, for example "optically variable" features exhibiting viewing angle dependent color have been proposed in the art as authentication means. Among them are figures (see Rudolf l. van renewe, "optical document Security" 2nd ed.,1998, the entire disclosure of which is incorporated herein by reference, chapter 10) and optical film Security devices (supra, chapter 13).

Another type of marking that attempts to prevent counterfeiting is cholesteric liquid crystals, which exhibit viewing angle dependent color. When illuminated with white light, the cholesteric liquid crystal structure reflects a predetermined color (predetermined wavelength) of light, which is a function of the material employed and typically varies with the viewing angle and device temperature. The precursor material itself is colorless and the observed color (predetermined wavelength range) is due solely to physical reflection of the cholesteric helical structure adopted by the liquid crystal material at a given temperature (see j.l. fergason, molecular crystals, vol.1, pp.293-307(1966), the entire disclosure of which is incorporated herein by reference). In particular, in liquid crystal materials (cholesteric liquid crystal polymers (CLCP)), the cholesteric helical structure is "frozen" in a predetermined state by polymerization, thus making it independent of temperature.

A chiral nematic liquid crystal phase is typically composed of nematic mesogenic molecules that contain chiral dopants, which create intermolecular forces that facilitate alignment of the molecules at a slight angle to each other. The result is a structure that can be seen as a very thin 2D nematic-like layer stack, where the facets of the layers are twisted with respect to the top and bottom. An important feature of the chiral nematic liquid crystal phase is the pitch p (see fig. 1). The pitch p is defined as the (vertical) distance that the facet makes one full revolution in the helix.

A characteristic property of the helical structure of the chiral nematic phase is its ability to selectively reflect light having a wavelength falling within a specific range. When this range overlaps a portion of the visible spectrum, a viewer will perceive a colored reflection. The center of the range is approximately equal to the pitch multiplied by the average index of refraction of the material. One parameter that has an effect on this spacing is temperature, which causes a change in the wavelength of the reflected light as a function of temperature due to the temperature dependence of the gradual change in the facet orientation (which modifies the spacing length) between successive layers. The pitch can be tightened by increasing the temperature of the molecules, thereby providing more heat energy to them and causing the angle of change of the facets to be larger. Similarly, decreasing the molecular temperature increases the pitch length of the chiral nematic liquid crystal. Other definitions of liquid crystalline polymers and liquid crystalline phases can be found in M.BarLo, Pure apple. chem.,2001, Vol.73, No.5, pp.845-895, the entire disclosure of which is incorporated herein by reference.

To improve the security level of chiral liquid crystal polymer films, a first idea that may emerge is to superimpose a code in the form of a pattern, symbol or barcode on the liquid crystal polymer film. However, there is always a risk that a counterfeiter will tamper with the code and apply it manually to the liquid crystal polymer film.

A second possibility to overcome this problem is to insert the code directly into the liquid crystal polymer film. For example, U.S. Pat. No. 6,207,240, the entire disclosure of which is incorporated herein by reference, describes an effect coating of a Cholesteric Liquid Crystal Polymer (CLCP) having a viewing-angle dependent reflective color, further comprising an absorbing pigment exhibiting a specific absorption color. Markings, such as symbols or text, are produced in the CLCP coating by laser irradiation. The laser radiation carbonizes the CLCP material in the irradiated area, and thus, the color of the substrate on which the CLCP is coated, or the color of the absorbing pigment blended into the CLCP, becomes visible in the irradiated area. However, this method requires a high power laser to carbonize the material to make the mark visible.

Another possibility is described in US 2006/0257633 A1, the entire disclosure of which is incorporated herein by reference, which applies not only to liquid crystal polymers, but also to polymers in general. The method comprises the following steps: an osmotic agent is applied to a predetermined area on the surface of a polymeric substrate and a supercritical fluid is contacted with the surface of the polymeric substrate to which the osmotic agent has been applied to cause the osmotic agent to permeate into the polymeric substrate. This method makes it possible to selectively (partially) modify a portion of the substrate surface. However, for industrial processes where high marking speeds are required for large numbers of articles, the method is complex and expensive to implement.

[ summary of the invention ]

The invention provides a liquid crystal polymer marking. The marking may be obtained by a method comprising the steps in the following order:

(i) applying a first chiral liquid crystal precursor composition on at least one surface of a (solid) substrate;

(ii) heating the coated first composition to bring it to a first chiral liquid crystal state;

(iii) applying (at least one) second chiral liquid crystal precursor composition to one or more regions of the applied first composition;

(iv) heating at least one of the one or more regions to bring it to a second chiral liquid crystal state;

(v) at least one of curing and polymerizing the first and second compositions.

In one aspect, one or both (preferably both) of the first and second chiral liquid crystal precursor compositions (and especially at least the first composition) may comprise (i) one or more (e.g. two, three, four, five or more, and especially at least two) different nematic compounds a and (ii) one or more (e.g. two, three, four, five or more) different chiral dopant compounds B which are capable of producing a cholesteric liquid crystal state of the chiral liquid crystal precursor composition upon heating. Furthermore, both the one or more nematic compounds a and the one or more chiral dopant compounds B may comprise at least one compound comprising at least one polymerizable group. For example, all of the one or more nematic compounds a and all of the one or more chiral dopant compounds B may comprise at least one polymerizable group. For example, the at least one polymerizable group may comprise a group capable of participating in free radical polymerization, in particular an (preferably activated) unsaturated carbon-carbon bond, such as of the formula H₂C = CH-C (O) -.

In another aspect of the inventive marking, at least one, and preferably both, of the first and second chiral liquid crystal precursor compositions (and especially the first composition) may comprise at least one chiral dopant compound B of formula (I):

wherein:

R₁、R₂、R₃、R₄、R₅、R₆、R₇and R₈Each independently represents C₁-C₆Alkyl and C₁-C₆An alkoxy group;

A₁and A₂Each independently represents a group of formulae (i) to (iii):

(i)–[(CH₂)_y-O]_z-C(O)-CH=CH₂；

(ii)–C(O)-D₁-O–[(CH₂)_y-O]_z-C(O)-CH=CH₂；

(iii)–C(O)-D₂-O–[(CH₂)_y-O]_z-C(O)-CH=CH₂；

D₁represents a group of the formula:

D₂represents a group of the formula:

m, n, o, p, q, r, s and t each independently represent 0, 1 or 2;

y represents 0, 1, 2,3, 4, 5 or 6;

if y equals 0 then z equals 0, and if y equals 1 to 6 then z equals 1.

In another aspect of the marking of the present invention, the first chiral liquid crystal precursor composition and the second chiral liquid crystal precursor composition can be the same. Alternatively, the first and second chiral liquid crystal precursor compositions may be different from each other. For example, the second chiral liquid crystal precursor composition may differ from the first chiral liquid crystal precursor composition at least in that the second composition comprises at least one of the one or more chiral dopant compounds B in a concentration different from the concentration of the same chiral dopant compound in the first composition, and/or at least in that the second composition comprises at least one chiral dopant compound B different from any of the one or more chiral dopant compounds B present in the first composition.

In yet another aspect of the marking of the present invention, the second chiral liquid crystal precursor composition may further comprise at least one pigment and/or dye that absorbs in the visible or invisible region of the electromagnetic spectrum, and/or may further comprise at least one luminescent pigment and/or dye.

In another aspect of the inventive marking, stage (ii) of the process may comprise heating the coated composition to a temperature of from about 55 ℃ to about 150 ℃, e.g., from about 55 ℃ to about 100 ℃, or from about 60 ℃ to about 100 ℃, and/or stage (iv) of the process may comprise heating at least one of the at least one or more regions to a temperature of from about 55 ℃ to about 150 ℃, e.g., from about 55 ℃ to about 100 ℃, or from about 60 ℃ to about 100 ℃.

In another aspect, stage (i) and/or (iii) of the method may comprise applying (e.g. depositing) the first or second chiral liquid crystal precursor composition by continuous ink jet printing and/or drop-on-demand ink jet printing and/or spray coating and/or valve jet printing.

In another aspect, the air flow may be passed over the surface of the one or more regions, preferably (substantially) parallel thereto, immediately after stage (iii) of the method.

In another aspect, the indicia of the invention may be in the form of at least one of: an image, a picture, a logo, a symbol, or a pattern presenting a code selected from one or more of a 1-dimensional barcode, a stacked 1-dimensional barcode, a 2-dimensional barcode, a 3-dimensional barcode, and a data matrix.

The invention also provides a substrate comprising (e.g. bearing on its surface) a marking of the invention as described above, including various aspects thereof.

In one aspect of the substrate, the mark may be used as at least one of a security component, an authenticity component, an identification component, and a tracking and tracing component.

In another aspect, the substrate may be or may comprise at least one of an identification document, a label, packaging, a banknote, a security document, a passport, a postage stamp, an ink-transfer film, and a reflective film.

The present invention also provides a security ink comprising: (i) one or more nematic compounds a and (ii) one or more chiral dopant compounds B capable of producing a cholesteric liquid crystal state of the security ink upon application of heat thereto.

In one aspect, the security ink may comprise at least one chiral dopant compound B of formula (I) as described above.

The present invention also provides a method of providing a substrate with a liquid crystal polymer marking. The method comprises the following steps in sequence:

(iv) heating at least one of the one or more regions to bring it to a second chiral liquid crystal state; and

(v) at least one of curing and polymerizing the first and second compositions.

The invention also provides a substrate comprising indicia, e.g. on at least one (outer) surface thereof. The indicia comprises a layer or film of a first chiral liquid crystal polymer having a first optical characteristic. The layer or film comprises in at least one region thereof a second liquid crystalline polymer having at least one second optical property different from the first optical property.

[ brief description of the drawings ]

The invention will be described in further detail by way of non-limiting examples of exemplary embodiments of the invention with reference to the following several figures, in which:

FIG. 1 is a schematic diagram illustrating nematic, rectangular and cholesteric liquid crystals;

FIG. 2 is a graph illustrating the spectral reflectance of a first chiral liquid crystal polymer, a second chiral liquid crystal polymer, and both polymers together;

figure 3 shows photographs of a marker according to the invention viewed from two different angles.

[ embodiment ] A method for producing a semiconductor device

The particulars shown herein are by way of example and for purposes of illustrative discussion of the specific embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.

The substrate used in the present invention is not particularly limited and may be of various types. For example, the substrate may consist of (essentially of) or comprise one or more of the following: metal (e.g., in the form of a container, such as a can for holding various items such as beverages or food), optical fiber, fabric, coatings and equivalents thereof, plastic materials, glass (e.g., in the form of a container, such as a bottle for holding various items such as beverages or food), cardboard, packaging, paper, and polymeric materials. It is noted that these substrate materials are given for illustrative purposes only and do not limit the scope of the present invention. The substrate will preferably have limited porosity (and may be substantially non-porous, for example).

The substrate will additionally advantageously have a dark or black surface or background on which the precursor composition is to be applied. Without wishing to be bound by any theory, it is speculated that in the case of a dark or black background, the light transmitted by the cholesteric liquid crystal material is mostly absorbed by the background, whereby any residual backscattering from the background does not interfere with the perception of the reflection of the cholesteric liquid crystal material itself by the naked eye. In contrast, the reflected color of cholesteric liquid crystal materials is less visible on substrates with light or white surfaces or backgrounds than on black or dark backgrounds, due to strong backscattering from the background. However, even in the case of a light or white background, cholesteric liquid-crystal materials can always be identified by means of circular-polarizing filters, since they selectively reflect only one of the two possible circular-polarizing components, depending on their chiral helical structure.

Non-limiting examples of suitable substrates include: cardboard darkened with black intaglio ink (no overprint varnish); cardboard darkened with black lithographic ink (no overprint varnish); cardboard darkened with any black ink and overprinted with aqueous varnish; cardboard darkened with any black ink and overprinted with solvent varnish; metal treated with black paint. In general, any (preferably non-porous and preferably black) substrate (which may not necessarily be flat and may be irregular) whose coating is insoluble or only slightly soluble in the solvents used in the chiral liquid precursor composition and the modifying agent is a suitable substrate for the purposes of the present invention.

The first chiral liquid crystal precursor composition for making a mark according to the invention and coated (e.g. deposited) on at least a portion of at least one surface of a substrate comprises a mixture of: (i) one or more nematic compounds a and (ii) one or more cholesteric (i.e. chiral dopant) compounds B (including cholesterol) capable of giving rise to cholesteric liquid crystal states of the composition. The pitch of the cholesteric liquid crystal states that can be obtained depends on the relative ratio of nematic to cholesteric compounds. Typically, the (total) concentration of the one or more nematic compounds a in the chiral liquid crystal precursor composition for use in the present invention will be about 5 to about 20 times the (total) concentration of the one or more cholesteric compounds B. In general, precursor compositions having high concentrations of cholesterol-type compounds are undesirable (although may be present in many cases) because the one or more cholesterol-type compounds tend to crystallize, thereby making it impossible to obtain the desired liquid crystal state having particular optical properties.

Nematic compounds a suitable for use in the first and second chiral liquid crystal precursor compositions employed according to the present invention are known in the art; when used alone (i.e., without the cholesterol-type compound), arrange themselves into a state characterized by birefringence. Non-limiting examples of nematic compounds A suitable for use in the present invention are described in, for example, WO93/22397, WO 95/22586, EP-B-0847432, U.S. Pat. No. 6,589,445, U.S. Pat. No. 2007/0224341A 1 and JP 2009-. The entire disclosures of these documents are incorporated herein by reference.

A preferred class of nematic compounds for use in the present invention comprises one or more (e.g. 1, 2 or 3) polymerizable groups per molecule which are the same or different from each other. Examples of polymerizable groups include groups capable of participating in free radical polymerization, and especially groups containing carbon-carbon double or triple bonds, such as acrylate moieties, vinyl moieties, or acetylene moieties. Particularly preferred as polymerizable groups are acrylate moieties.

The nematic compounds used in the present invention may additionally comprise one or more (e.g. 1, 2,3, 4, 5 or 6) optionally substituted aromatic groups, preferably phenyl groups. Examples of optional substituents for the aromatic group include examples of substituents on the phenyl ring described herein as chiral dopant compounds of formula (I), such as alkyl and alkoxy.

Examples of groups that may optionally be present to link the polymerizable group and the aryl group (e.g., phenyl) in the nematic compound a include those exemplified herein for chiral dopant compound B of formula (I), including those of formula (IA) and formula (IB) described below. For example, the nematic compound A may comprise one or more compounds having the formula (I) (and formula (IA) as described above for formula (I)And A in the formula (IB))₁And A₂The indicated meanings and typically are bonded to the groups of formulae (i) to (iii) of optionally substituted phenyl. Specific non-limiting examples of nematic compounds suitable for use in the present invention are given in the examples below.

The one or more nematic compounds a (and the one or more chiral dopant compounds B) used in the present invention are preferably substantially free of compounds which do not contain any polymerizable group (i.e. preferably contain compounds which do not contain any polymerizable group, if any, merely as impurities). The nematic compounds are preferably also different from the cellulose derivatives.

The one or more cholesteric (i.e. chiral dopant) compounds B for use in the present invention preferably comprise at least one polymerizable group.

As described above, suitable examples of the one or more chiral dopant compounds B include formula (I):

wherein:

A₁and A₂Each independently represents a group of formulae (i) to (iii):

(i)–[(CH₂)_y-O]_z-C(O)-CH=CH₂；

(ii)–C(O)-D₁-O–[(CH₂)_y-O]_z-C(O)-CH=CH₂；

(iii)–C(O)-D₂-O–[(CH₂)_y-O]_z-C(O)-CH=CH₂；

D₁represents a group of the formula:

D₂represents a group of the formula:

m, n, o, p, q, r, s and t each independently represent 0, 1 or 2;

y represents 0, 1, 2,3, 4, 5 or 6;

if y equals 0 then z equals 0, and if y equals 1 to 6 then z equals 1.

In one aspect, the one or more chiral dopant compounds B may comprise one or more didehydromannitol derivatives of formula (IA):

wherein:

A₁and A₂Each independently represents a group of formulae (i) to (iii):

(i)–[(CH₂)_y-O]z-C(O)-CH=CH₂；

(ii)–C(O)-D₁-O–[(CH₂)y-O]z-C(O)-CH=CH₂；

(iii)–C(O)-D₂-O–[(CH₂)y-O]z-C(O)-CH=CH₂；

D₁represents a group of the formula:

D₂represents a group of the formula:

m, n, o, p, q, r, s and t each independently represent 0, 1 or 2;

y represents 0, 1, 2,3, 4, 5 or 6;

if y equals 0 then z equals 0, and if y equals 1 to 6 then z equals 1.

In one embodiment of the compounds of formula (IA) (and compounds of formula (I)), R₁、R₂、R₃、R₄、R₅、R₆、R₇And R₈Each independently represents C₁-C₆An alkyl group. In an alternative embodiment, R in formula (IA) (and formula (I)) is₁、R₂、R₃、R₄、R₅、R₆、R₇And R₈Each independently represents C₁-C₆An alkoxy group.

In another embodiment of the compounds of formula (I) and formula (IA), A₁And A₂Each independently of the other, of the formula- [ (CH)₂)_y-O]_z-C(O)-CH=CH₂A group; r₁、R₂、R₃And R₄Each independently represents C₁-C₆An alkyl group; and m, n, o and p each independently represent 0, 1 or 2. In yet another embodiment, in formula (I) and formula (IA)A of (A)₁And A₂Each independently of the other, of the formula- [ (CH)₂)_y-O]_z-C(O)-CH=CH₂A group; r₁、R₂、R₃And R₄Each independently represents C₁-C₆An alkoxy group; and m, n, o and p each independently represent 0, 1 or 2.

In another embodiment of the compounds of formula (IA) (and formula (I)), A₁And A₂Each independently of the other, of the formula-C (O) -D₁-O-[(CH₂)_y-O]_z-C(O)-CH=CH₂And/or of the formula-C (O) -D₂-O-[(CH₂)_y-O]_z-C(O)-CH=CH₂A group of (a); and R is₁、R₂、R₃、R₄、R₅、R₆、R₇And R₈Each independently represents C₁-C₆An alkyl group. In an alternative embodiment, A in formula (IA) (and formula (I)) is₁And A₂Each independently of the other, of the formula-C (O) -D₁-O-[(CH₂)_y-O]_z-C(O)-CH=CH₂A group and/or a compound of the formula-C (O) -D₂-O-[(CH₂)_y-O]_z-C(O)-CH=CH₂A group; and R is₁、R₂、R₃、R₄、R₅、R₆、R₇And R₈Each independently represents C₁-C₆An alkoxy group.

In another aspect, the one or more chiral dopant compounds B may comprise one or more sorbitan (isosorbide) derivatives represented by formula (IB):

wherein:

A₁and A₂Each independently represents a group of formulae (i) to (iii):

(i)–[(CH₂)_y-O]_z-C(O)-CH=CH₂；

(ii)–C(O)-D₁-O–[(CH₂)_y-O]_z-C(O)-CH=CH₂；

(iii)–C(O)-D₂-O–[(CH₂)_y-O]_z-C(O)-CH=CH₂；

D₁represents a group of the formula:

D₂represents a group of the formula:

m, n, o, p, q, r, s and t each independently represent 0, 1 or 2;

y represents 0, 1, 2,3, 4, 5 or 6;

if y equals 0 then z equals 0, and if y equals 1 to 6 then z equals 1.

In one embodiment of the compound of formula (IB), R₁、R₂、R₃、R₄、R₅、R₆、R₇And R₈Each independently represents C₁-C₆An alkyl group. In an alternative embodiment, R in formula (IB)₁、R₂、R₃、R₄、R₅、R₆、R₇And R₈Each independently represents C₁-C₆An alkoxy group.

In another embodiment of the compounds of formula (IB), A₁And A₂Each independently of the other, of the formula- [ (CH)₂)_y-O]_z-C(O)-CH=CH₂A group; r₁、R₂、R₃And R₄Each independently represents C₁-C₆An alkyl group; and m, n, o and p each independently represent 0, 1 or 2. In yet another embodiment, A in formula (IB)₁And A₂Each independently of the other, of the formula- [ (CH)₂)_y-O]_z-C(O)-CH=CH₂A group; r₁、R₂、R₃And R₄Each independently represents C₁-C₆An alkoxy group; and m, n, o and p each independently represent 0, 1 or 2.

In another embodiment of the compounds of formula (IB), A₁And A₂Each independently of the other, of the formula-C (O) -D₁-O-[(CH₂)_y-O]_z-C(O)-CH=CH₂And/or of the formula-C (O) -D₂-O-[(CH₂)_y-O]_z-C(O)-CH=CH₂A group of (a); and R is₁、R₂、R₃、R₄、R₅、R₆、R₇And R₈Each independently represents C₁-C₆An alkyl group. In an alternative embodiment, A in formula (IB)₁And A₂Each independently of the other, of the formula-C (O) -D₁-O-[(CH₂)_y-O]_z-C(O)-CH=CH₂A group and/or a compound of the formula-C (O) -D₂-O-[(CH₂)_y-O]_z-C(O)-CH=CH₂A group; and R is₁、R₂、R₃、R₄、R₅、R₆、R₇And R₈Each independently represents C₁-C₆An alkoxy group.

In a preferred embodiment, R in formulae (I), (IA) and (IB)₁、R₂、R₃、R₄、R₅、R₆、R₇And R₈The alkyl and alkoxy groups of (a) may contain 3,4, 6 or 7 carbon atoms, especially 4 or 6 carbon atoms.

Examples of the alkyl group having 3 or 4 carbon atoms include isopropyl group and butyl group. Examples of the alkyl group having 6 or 7 carbon atoms include hexyl group, 2-methylpentyl group, 3-methylpentyl group, 2-dimethylpentyl group and 2, 3-dimethylpentyl group.

Examples of the alkoxy group having 3 or 4 carbon atoms include isopropoxy, but-1-oxy, but-2-oxy and t-butoxy. Examples of the alkoxy group having 6 or 7 carbon atoms include hex-1-oxy, hex-2-oxy, hex-3-oxy, 2-methylpent-1-oxy, 2-methylpent-2-oxy, 2-methylpent-3-oxy, 2-methylpent-4-oxy, 4-methylpent-1-oxy, 3-methylpent-2-oxy, 3-methylpent-3-oxy, 2-dimethylpent-1-oxy, 2-dimethylpent-3-oxy, 2-dimethylpent-4-oxy, 4-dimethylpent-1-oxy, 2-dimethylpent-4-oxy, 2-dimethylpent-1-oxy, 2-dimethylp, 2, 3-dimethylpent-1-yloxy, 2, 3-dimethylpent-2-yloxy, 2, 3-dimethylpent-3-yloxy, 2, 3-dimethylpent-4-yloxy and 3, 4-dimethylpent-1-yloxy.

Non-limiting specific examples of chiral dopant compounds B of formula (I) for use in the present invention are provided in the examples below.

The one or more chiral dopant compounds B will generally be present at a total concentration of about 0.1 wt% to about 30 wt%, for example about 0.1 wt% to about 25 wt%, or about 0.1 wt% to about 20 wt%, based on the total weight of the composition. Optimum results are generally obtained at concentrations of from 3 wt% to 10 wt%, for example from 5 wt% to 8 wt%, based on the total weight of the precursor composition. The one or more nematic compounds a will generally be present in a concentration of from about 30% to about 50% by weight, based on the total weight of the precursor composition.

In the marking according to the invention, the application (e.g. deposition) of the first precursor composition (and preferably also of the second precursor composition) is preferably carried out with a printing technique, in particular a printing technique selected from at least one of continuous ink-jet printing, drop-on-demand ink-jet printing and spray coating. Of course, other printing techniques known to those skilled in the art of printing may also be used. In a preferred embodiment, ink jet printing is used. Industrial inkjet printers, which are commonly used for numbering, coding and marking applications on conditioning lines and printing presses, are particularly suitable. Preferred ink jet printers include single nozzle continuous ink jet printers (also known as line-by-line or multi-layer offset printers) and drop-on-demand ink jet printers, especially valve type ink jet printers. The thickness of the applied precursor composition (especially the first precursor composition) will typically be from about 3 to about 20 μm, for example from about 5 to about 15 μm.

In particular, if the precursor composition is to be applied by a printing technique as described above, for example by inkjet printing, the composition will generally comprise a solvent in order to adjust its viscosity to a value suitable for the application (printing) technique employed. Typical viscosity values of the ink jet printing ink at 25 ℃ are in the range of about 4 to about 30 mpa.s. Suitable solvents are known to those skilled in the art. Non-limiting examples thereof include low viscosity, slightly polar and aprotic organic solvents such as Methyl Ethyl Ketone (MEK), acetone, ethyl acetate, ethyl 3-ethoxypropionate, toluene and mixtures of two or more thereof.

Furthermore, in particular, if the precursor composition is to be applied by continuous inkjet printing, the precursor composition used in the present invention will generally also comprise at least one conductive agent (e.g. a salt). The conductive agent will have a non-negligible solubility in the composition. Non-limiting examples of suitable conductivity agents include salts such as tetraalkylammonium salts (e.g., tetrabutylammonium nitrate, tetrabutylammonium perchlorate, and tetrabutylammonium hexafluorophosphate), alkali metal thiocyanates such as potassium thiocyanate, and alkali metal perchlorates such as lithium perchlorate. The conductive agent will be present in a concentration sufficient to provide the desired or desirable conductivity. Of course, mixtures of two or more different conductive agents (salts) may be used.

If the chiral liquid crystal precursor composition used in the present invention is to be cured/polymerized by UV irradiation, the composition will also comprise at least one photoinitiator showing a non-negligible solubility in the composition. Non-limiting examples of many suitable photoinitiators include alpha-hydroxy ketones, such as 1-hydroxy-cyclohexyl-phenyl-ketone and mixtures of 1-hydroxy-cyclohexyl-phenyl-ketone with one or more of diphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and 2-hydroxy-1- [4- (2-hydroxyethoxy) phenyl ] -2-methyl-1-propanone (e.g., about 1: 1); phenylglyoxylates such as methyl benzoylformate and mixtures of oxy-phenyl-acetic acid 2- [ 2-oxo-2-phenyl-acetoxy-ethoxy ] -ethyl ester and oxy-phenyl-acetic acid 2- [ 2-hydroxy-ethoxy ] -ethyl ester; benzyl dimethyl ketals such as α, α -dimethoxy- α -phenylacetophenone; α -aminoketones such as 2-benzyl-2- (dimethylamino) -1- [4- (4-morpholinyl) phenyl ] -1-butanone and 2-methyl-1- [4- (methylthio) phenyl ] -2- (4-morpholinyl) -1-propanone; phosphine oxides and phosphine oxide derivatives such as diphenyl (2,4, 6-trimethylbenzoyl) -phosphine oxide; phenylbis (2,4, 6-trimethylbenzoyl) supplied by Ciba; and 9-oxathiacanthane (thiochromene) derivatives, such as Speedcure ITX (CAS 142770-42-1), Speedcure DETX (CAS 82799-44-8), Speedcure CPTX (CAS 5495-84-1-2 or CAS 83846-86-0) supplied by Lambson.

If the precursor composition is to be cured by a method other than irradiation with UV light, such as by high energy particles (e.g. electron beam), X-rays, gamma rays, etc., the use of a photoinitiator may of course be dispensed with.

The chiral liquid crystal precursor compositions used in the present invention may also comprise a variety of other optional components that are suitable and/or desirable for achieving the particular desired characteristics of the composition, and in general, may comprise any components/materials that do not adversely affect the desired characteristics of the precursor composition to any significant extent. Non-limiting examples of such optional components are resins, silane compounds, sensitizers for photoinitiators (if present), and the like. For example, the composition may include one or more silane compounds that exhibit non-negligible solubility in the composition. Non-limiting examples of suitable silane compounds include optionally polymerizable silanes such asFormula R₁R₂R₃-Si-R₄In which R is₁、R₂And R₃Independently represent alkoxy and alkoxyalkoxy having a total of from 1 to about 6 carbon atoms, and R₄Represents a vinyl group, an allyl group, or (C)_1-10) Alkyl, (methyl) propionyloxy (C)_1-6) Alkyl and glycidyloxy (C)_1-6) Alkyl radicals such as vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris (2-methoxyethoxy) silane, 3-methylpropanoxypropyltrimethoxysilane, octyltriethoxysilane and 3-glycidoxypropyltriethoxysilane from EvonikA family.

The concentration of the one or more silane compounds, if present, in the precursor composition will generally be from about 0.5% to about 5% by weight, based on the total weight of the composition.

After coating (e.g. deposition) the first chiral liquid crystal precursor composition according to the invention onto a substrate, the precursor composition is brought into a chiral liquid crystal state having specific optical properties. To this end, the chiral liquid crystal precursor composition is heated to evaporate the solvent (if present) contained in the composition and to bring about the desired chiral liquid crystal state. The temperature used to evaporate the solvent and to cause the formation of the first liquid crystal state depends on the components of the first chiral liquid crystal precursor composition and in many cases will be in the range of about 55 ℃ to about 150 ℃, for example about 55 ℃ to about 100 ℃, preferably about 60 ℃ to about 100 ℃. Examples of suitable heating sources include conventional heating means and especially radiation sources, such as IR lamps. In many cases, a heating time of about 1 second to about 30 seconds, such as no more than about 20 seconds, no more than about 10 seconds, or no more than about 5 seconds, will be sufficient.

The term "specific optical properties" is to be understood as a liquid crystalline state having a specific pitch reflecting a specific wavelength range. An advantage of precursor compositions containing chiral dopant compounds according to formula (I) and related formulae is the ability to rapidly produce a stable liquid crystal state upon heating (and evaporation of the solvent). In contrast, the liquid crystalline state obtained with the precursor compositions of the prior art (see, for example, EP 1299375, EP 1669431 and EP 1339812, the entire disclosures of which are incorporated herein by reference) after heating and evaporation of the solvent can often be disturbed by small temperature changes. Therefore, to maintain the stability of the liquid crystal state, it is necessary in the latter case to solidify or fix the liquid crystal state by an at least partial curing or polymerization procedure. As described previously, when the liquid crystal state is solidified or fixed, generation of a code or mark within the mark becomes difficult. In contrast, in the method of making a marking according to the present invention, no curing/polymerization of the components of the precursor composition is performed prior to step (v). In other words, the curing/polymerization procedure is only performed after the first and second chiral liquid crystal states have been reached.

After application of the first chiral liquid crystal precursor composition and formation of the first chiral liquid crystal state (which may be in the form of a layer, pattern or film, for example), the (at least one) second chiral liquid crystal precursor composition is applied onto one or more areas of the applied first composition in the first chiral liquid crystal state. The second chiral liquid crystal precursor composition can be applied while the first chiral liquid crystal precursor composition is still in a heated state (e.g., immediately after the heating operation is completed) or can be applied after the first chiral liquid crystal precursor composition has cooled to at least some extent (e.g., at substantially room temperature). If necessary, cooling of the first precursor composition may be accelerated by means known to those skilled in the art, such as by blowing ambient air onto the previously heated composition. Applying the second chiral liquid crystal precursor composition to the first precursor composition in a cooled state can improve the resolution of the marking. On the other hand, if the entire procedure of making the marking is to be carried out in as simple and fast a manner as possible, it may be desirable to apply the second chiral liquid crystal precursor composition immediately after the heating operation is completed.

The second chiral liquid crystal precursor composition applied in one or more areas on the first chiral liquid precursor composition in the first chiral liquid crystal state may be the same as or different from the first chiral liquid crystal precursor composition. In addition, each of the aspects (e.g., components, coating methods, etc.) described above with respect to the first chiral liquid crystal precursor composition are equally or uniformly applicable to the second chiral liquid crystal precursor composition. For example, as in the case of the first chiral liquid crystal precursor composition, the one or more chiral dopant compounds B will typically be present in the second chiral liquid crystal precursor composition at a total concentration of about 0.1 wt% to about 30 wt%, for example about 0.1 wt% to about 25 wt%, or about 0.1 wt% to about 20 wt%, based on the total weight of the second composition. Likewise, the one or more nematic compounds a will typically be present in the second chiral liquid crystal precursor composition at a concentration of from about 30% to about 50% by weight, based on the total weight of the second precursor composition.

If the second chiral liquid crystal precursor composition is different from the first chiral liquid crystal precursor composition, the one or more differences may relate to, for example, one or more of compounds a and B present in these compositions and/or to the concentration of one or more of these compounds. For example, the difference or the only difference between these compositions may be that one or more (or all) chiral dopant compounds B are present in the second composition at a concentration different from the corresponding concentration in the first composition. Furthermore, the difference or the only difference between the first and second compositions may be that the one or more chiral dopant compounds B in the first composition have formula (I) and/or related formulae as described above, while at least one of the one or more chiral dopant compounds B in the second composition is different from formula (I) and/or related formulae. For example, at least one of the one or more chiral dopant compounds B in the second composition may be a di-anhydrosorbitol or di-anhydromannitol derivative as described, for example, in EP-B-0847432, GB-A-2330139, and U.S. Pat. No. 6,589,445, the entire disclosure of which is incorporated herein by reference.

After applying (e.g., depositing) a second chiral liquid crystal precursor composition to one or more regions of a first chiral liquid crystal precursor composition in a first chiral liquid crystal state having a first particular optical characteristic, the second precursor composition is brought to a second chiral liquid crystal state having a second particular optical characteristic. To this end, at least a portion of one or more regions onto which the second chiral liquid crystal precursor composition has been applied are heated, the solvent (if present) contained in the composition is evaporated and the desired second chiral liquid crystal state is promoted. The temperature used to evaporate the solvent and promote the formation of the second liquid crystal state depends on the components of the second chiral liquid crystal precursor composition and in many cases will be in the range of from about 55 ℃ to about 150 ℃, for example from about 55 ℃ to about 100 ℃, preferably from about 60 ℃ to about 100 ℃. Examples of suitable heating sources include conventional heating means, and in particular radiation sources such as IR lamps.

It will be appreciated that the marking according to the invention is different or not corresponding to a simple overlap of two chiral nematic liquid crystal layers. This constitutes a significant difference and significant advantage over the prior art. In particular, when the first chiral liquid crystal precursor composition is deposited on a substrate and brought into a first chiral liquid crystal state, this state is characterized by a pitch p 1. Likewise, when a second chiral liquid crystal precursor composition is deposited on one or more regions of the coated first composition and brought into a second chiral liquid crystal state, the second state is characterized by a pitch p2 (which may be the same as or different from p 1). In this connection, it is to be noted that the product obtained after stage (iv) of the process of the invention and further cured/polymerized in stage (v) is not an overlap of the first chiral liquid crystal state having a pitch p1 and the second chiral liquid crystal state having a pitch p 2. Instead, the region bearing the second chiral liquid crystal precursor composition, once in the second chiral liquid crystal state, has a pitch p2' that is different from p1 and p2 but depends to some extent on the nature of p 1. Without wishing to be bound by any theory, it is speculated that the first chiral liquid crystal state has an effect on the formation of the second chiral liquid crystal state. The induction of the second chiral liquid crystal precursor composition by the first chiral liquid crystal state will accelerate and promote a second chiral liquid crystal state different from the chiral liquid crystal state expected based on only the second chiral liquid crystal precursor composition alone. This constitutes a significant difference and a significant advantage over the prior art which discloses a simple overlap of two different layers of two different chiral liquid crystal states as a marking or code.

The marking according to the invention is controlled by a first chiral liquid crystal precursor composition known only to the maker of the marking. A large number of specific tags and codes can be generated from different first chiral liquid crystal precursor compositions and stored in a specific database containing all the generated tags or codes. Without wishing to be bound by any theory, it is speculated that the second precursor composition will induce a very local and controlled recombination of the first chiral liquid crystal state. It should also be noted that the process of the invention is industrially fast and easy to implement and does not require complex means.

The area of the coated first precursor composition on which the second precursor composition is coated will typically be from about 0.1% to about 99.9% of the total area of the coated first precursor composition. The area will typically be at least about 1%, such as at least about 5% or at least about 10%, and not more than about 99%, such as not more than about 95% or not more than about 90% of the total area of the first precursor composition being applied.

The marking according to the invention may be in the form of: images, pictures, logos, signs, and/or patterns representing (1D, 2D, 3D) codes, such as 1-dimensional barcodes, stacked 1-dimensional barcodes, 2-dimensional barcodes, 3-dimensional barcodes, and/or data matrices. An example of a corresponding marker is represented by fig. 2.

Of course, it is possible to use more than one second precursor composition (e.g., two, three, or more different second precursor compositions) and apply them simultaneously and/or sequentially on the applied first precursor composition (e.g., in different areas of the applied first precursor composition). For example, it is also possible to apply a second precursor composition and then apply a different second precursor composition in at least a portion of the areas where the second precursor composition was initially applied (and optionally, in one or more areas where the second precursor composition was not initially applied).

In order to enhance the security of the marking according to the invention, the second chiral liquid crystal precursor composition may additionally comprise one or more pigments and/or dyes that absorb in the visible or invisible region of the electromagnetic spectrum, and/or may additionally comprise one or more luminescent pigments and/or dyes. Non-limiting examples of suitable pigments and/or dyes that absorb in the visible or invisible region of the electromagnetic spectrum include phthalocyanine derivatives. Non-limiting examples of suitable luminescent pigments and/or dyes include lanthanide derivatives. The presence of pigments and/or dyes will enhance and strengthen the security of the marking against counterfeiting. Of course, in addition to the components discussed above, the second chiral liquid crystal precursor composition used in the present invention may comprise any other components/materials that do not adversely affect the desired properties of the second chiral liquid crystal precursor composition to any significant extent.

In the marking according to the invention, the deposition of the second precursor composition on one or more areas of the first chiral liquid crystal precursor composition in the first liquid crystal state is preferably carried out with a printing technique and in particular a technique selected from continuous ink jet printing, drop-on-demand ink jet printing, valve jet printing and spray coating. The advantage, especially compared to prior art techniques using lasers or extractants for polymerized or partially polymerized liquid crystals, is the speed and ease of mark formation, which is generated in almost real time. Another advantage of using the above printing techniques is the accuracy and stability of the marks formed in the chiral liquid crystal state. Another advantage of using this printing technique is the almost unlimited possibility of marks that can be generated and changed in almost real time. In a preferred embodiment, the second precursor composition is applied using ink jet technology. Industrial inkjet printers, which are commonly used for numbering and coding and marking applications on conditioning lines and printers, are particularly suitable. Preferred ink jet printers are single nozzle continuous ink jet printers (also known as line-by-line or multi-layer offset printers) and drop-on-demand ink jet printers, especially valve ink jet printers.

In order to improve the resolution of the applied indicia, it will generally be advantageous to pass a stream of air over the surface of the applied first precursor composition, preferably (substantially) parallel thereto, immediately after the second precursor composition is applied to one or more areas of the first precursor composition. The air flow may be generated by any means, for example in an (industrial) air dryer. The air flow will preferably not be vigorous and/or high velocity. The temperature of the air will typically be ambient (e.g., about 20 ℃), but may also be slightly lower or higher, e.g., up to about 60 ℃, up to about 40 ℃, or up to about 30 ℃. The term "immediately after application of the second precursor composition" means without delay, e.g., for a period of no more than about 10 seconds, e.g., no more than about 5 seconds, no more than about 3 seconds, no more than about 2 seconds, or no more than about 1 second, after application of the second precursor composition is complete.

The marking according to the invention is finally obtained by curing and/or polymerizing a composition in a first chiral liquid crystal state, wherein the first composition has been locally modified (in one or more areas) by application of a second precursor composition in a second chiral liquid crystal state. The fixing or hardening is preferably carried out by irradiation with UV light, which induces polymerization of the polymerizable groups present in the precursor composition. In contrast to the prior art described above, the marking according to the invention is easy to implement industrially and reliable.

Fig. 2 clearly demonstrates that the spectral reflectance of the cured product in the region where the second chiral liquid crystal precursor composition has been applied is not the sum of the two spectral reflectances of the chiral liquid crystal precursor compositions taken independently, even when the first and second precursor compositions are the same.

Another advantage of the marking according to the invention is that the natural random variations inherently present in the printing program according to the invention can be used as a unique identifier ("fingerprint") which is hardly reproducible. In this regard, it should be appreciated that the cured and/or polymerized first precursor composition in the chiral liquid crystal state is a marking even if the second precursor composition is not coated. In other words, the second precursor composition is used to create "in/on mark".

For example, a marking according to the present invention may incorporate security features, authenticity features, identification features, or tracking and tracing features. An example of a security feature is a public feature with a 3D effect.

The following examples are intended to illustrate the invention without limiting it.

Examples

The markers according to the invention were prepared as follows:

(1) preparation of a first chiral liquid Crystal precursor composition

Chiral liquid crystal precursor composition (1) was prepared as follows:

chiral dopant compound B of formula (I) shown above (i.e. bis (4- (4- (acryloyloxy) -3-methoxybenzoyloxy) -3-methoxy-benzoic acid) (3R,3aR,6R,6aR) -hexahydrofuro [3, 2-B)]Furan-3, 6-diester) (7.5 g), nematic compound a1 (i.e. benzoic acid 4- [ [ [4- [ (1-pendant oxy-2-propen-1-yl) oxy)]Butoxy radical]Carbonyl radical]Oxy radical]-1,1' - (2-methyl-1, 4-phenylene) ester) (22.0 g), nematic compound a2 (i.e. bis (4- (4- (acryloyloxy) butoxy) -benzoic acid) 2-methyl-1, 4-phenylene ester) (14.0 g) and acetone (49.9 g) were weighed into a screwable flask, which was then heated in an oven until a light brown solution was obtained. Tetrabutylammonium perchlorate (0.6 g), lithium perchlorate (0.3 g), 2-methyl-1 [4- (methylthio) phenyl ] was then added to the mixture]-2-morpholinylpropan-1-one (from Ciba)1.3 g), 2, 4-diethyl-sulfur-9-one (0.7 g) and vinyltriethoxysilane (3.7 g). The final mixture is then stirred or shaken until complete dissolution is achieved, yielding chiral liquid crystal precursor composition (1).

The chiral liquid crystal precursor composition (2) was prepared as follows:

chiral dopant compound B of formula (I) shown above (i.e., 4- (4- (acryloyloxy) benzoyloxy) -3-methoxybenzoic acid (3R,3aR,6R,6aR) -6- (4- (4- (acryloyloxy) -3-methoxybenzoyloxy) hexahydrofuro [3,2-B]Furan-3-ester) (9.0 g), nematic compound A1 (i.e. benzoic acid 4- [ [ [4- [ (1-pendant oxy-2-propen-1-yl) oxy)]Butoxy radical]Carbonyl radical]Oxy radical]-1,1' - (2-methyl-1, 4-phenylene) ester) (16.0 g), nematic compound a2 (i.e. bis (4- (4- (acryloyloxy) butoxy) -benzoic acid) 2-methyl-1, 4-phenylene ester) (20.0 g) and methyl ethyl ketone (48.0 g) were weighed into a screwable flask, which was then heated in an oven until a light brown solution was obtained. Tetrabutylammonium perchlorate (0.5 g), lithium perchlorate (0.6 g) and 2-methyl-1 [4- (methylthio) phenyl group were then added to the mixture]-2-morpholinylpropan-1-one (from Ciba)1.2 g), 2-isopropyl-sulfur-9-one (0.7 g) and vinyltriethoxysilane (4.0 g). The final mixture is then stirred or shaken until complete dissolution is achieved, yielding chiral liquid crystal precursor composition (2).

(2) Deposition of a first chiral liquid crystal precursor composition on a substrate

The chiral liquid crystal precursor composition (1) or (2) was then used to print a planar pattern by continuous inkjet printing on a paper substrate with a black background.

(3) Bringing the first precursor composition into a first chiral liquid crystal state

A chiral liquid crystal state is formed from the planar pattern by exposure to an IR lamp for about 1 to 5 seconds, depending on the substrate.

(4) Applying a second precursor composition to one or more regions of the deposited first composition

A mark or design is then printed on top of the deposited precursor composition in the first chiral liquid crystal state using a continuous ink jet printer. The air flow is made to flow parallel to the printing surface within about 1 second after the printing procedure is completed. The inkjet ink is the same as the precursor composition of step (1) (i.e., the same as chiral liquid crystal precursor composition (1) or the same as chiral liquid crystal precursor composition (2)).

(5) Bringing a second chiral precursor composition into a second chiral liquid crystal state having a different first optical property

The second chiral liquid crystal state in the area on which the code or design is printed is formed by exposing the resulting product (including the indicia) to an IR lamp for about 1 to 5 seconds (depending on the substrate). This locally results in a novel anisotropic behavior different from the first one.

(6) Curing or polymerizing the resultant product

Then passing through a UV light source with UV irradiation degree of 10mW/cm²The resulting product with the indicia printed thereon was cured by a UV dryer of a low pressure mercury lamp.

An example of a product with a label obtained by the above procedure is shown in fig. 3.

For example, the following other compounds may be used in the above procedure instead of the chiral dopant compound B of formula (I):

bis (4- (4 (acryloyloxy) benzoyloxy) -benzoic acid) (3R,3aR,6R,6aR) -hexahydrofuro [3,2-b ] furan-3, 6-diester;

bis (4- (4- (acryloyloxy) butoxy) -benzoic acid) (3R,3aR,6R,6aR) -hexahydrofuro [3,2-b ] furan-3, 6-diester;

bis (4- (acryloyloxy) -2-methyl-benzoic acid) (3R,3aR,6R,6aR) -hexahydrofuro [3,2-b ] furan-3, 6-diester;

bis (4- (4- (acryloyloxy) benzoyloxy) -3-methoxybenzoic acid) (3R,3aR,6S,6aR) -hexahydrofuro [3,2-b ] furan-3, 6-diester;

bis (4- (4- (acryloyloxy) -3-methoxy-benzoyloxy) benzoic acid) (3R,3aR,6R,6aR) -hexahydrofuro [3,2-b ] furan-3, 6-diester;

bis (4- (4 (acryloyloxy) benzoyloxy) -3-methoxybenzoic acid) (3R,3aR,6R,6aR) -hexahydrofuro [3,2-b ] furan-3, 6-diester;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -benzoyl ] oxy } -3-methoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -2-methylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -2, 5-dimethylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) -2, 5-dimethylbenzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxy-5-methylbenzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methoxybenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } benzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methoxybenzoyl ] oxy } benzoyl) -1,4:3, 6-didehydro-D-mannitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -3-methoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } -2, 5-dimethylbenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methoxybenzoyl ] oxy } -3-methylbenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } -2-methylbenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methoxybenzoyl ] oxy } -3-methylbenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxy-5-methylbenzoyl ] oxy } -2-methylbenzoyl) -5-O- (4- { [4- (acryloyloxy) -5-methoxy-2-methylbenzoyl ] oxy } -3-methylbenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-ethoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-ethoxybenzoyl ] oxy } benzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-ethoxy-5-methylbenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-ethoxybenzoyl ] oxy } benzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-ethoxy-5-methylbenzoyl) -5-O- (4- { [4- (acryloyloxy) -5-ethoxy-2-methylbenzoyl ] oxy } benzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) -3-ethoxybenzoyl ] oxy } benzoyl) -5-O- (4- { [4- (acryloyloxy) -2-methylbenzoyl ] oxy } -2-ethoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2-O- (4- { [4- (acryloyloxy) -2, 5-dimethylbenzoyl ] oxy } -2-ethoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -2-methylbenzoyl ] oxy } -2-ethoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -2, 5-dimethylbenzoyl ] oxy } -2-ethoxybenzoyl) -1,4:3, 6-didehydro-D-mannitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -2-ethoxybenzoyl ] oxy } -2-ethoxybenzoyl) -1,4:3, 6-dianhydro-D-mannitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } -2-ethoxybenzoyl) -1,4:3, 6-dianhydro-D-mannitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -2-ethoxybenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-dianhydro-D-mannitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -2-ethoxybenzoyl ] oxy } -3-methylbenzoyl) -1,4:3, 6-dianhydro-D-mannitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -2-ethoxybenzoyl ] oxy } -3-methoxybenzoyl) -1,4:3, 6-dianhydro-D-mannitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -3-methoxybenzoyl ] oxy } -3-methoxybenzoyl) -1,4:3, 6-dianhydro-D-mannitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -3-methoxybenzoyl ] oxy } -3-methoxybenzoyl) -1,4:3, 6-dianhydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -benzoyl ] oxy } -3-methoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -2-methylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -2, 5-dimethylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) -2, 5-dimethylbenzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxy-5-methylbenzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methylbenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -3-methoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } -2-methoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methoxybenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } benzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methoxybenzoyl ] oxy } benzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } -2, 5-dimethylbenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methoxybenzoyl ] oxy } -3-methylbenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } -2-methylbenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-methoxybenzoyl ] oxy } -3-methylbenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) -2-methoxy-5-methylbenzoyl ] oxy } -2-methylbenzoyl) -5-O- (4- { [4- (acryloyloxy) -5-methoxy-2-methylbenzoyl ] oxy } -3-methylbenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-ethoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-ethoxybenzoyl ] oxy } benzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-ethoxy-5-methylbenzoyl) -5-O- (4- { [4- (acryloyloxy) -3-ethoxybenzoyl ] oxy } benzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) benzoyl ] oxy } -2-ethoxy-5-methylbenzoyl) -5-O- (4- { [4- (acryloyloxy) -5-ethoxy-2-methylbenzoyl ] oxy } benzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) -3-ethoxybenzoyl ] oxy } benzoyl) -5-O- (4- { [4- (acryloyloxy) -2-methylbenzoyl ] oxy } -2-ethoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2-O- (4- { [4- (acryloyloxy) -2, 5-dimethylbenzoyl ] oxy } -2-ethoxybenzoyl) -5-O- (4- { [4- (acryloyloxy) -2-methylbenzoyl ] oxy } -2-ethoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -2, 5-dimethylbenzoyl ] oxy } -2-ethoxybenzoyl) -1,4:3, 6-didehydro-D-glucitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -2-ethoxybenzoyl ] oxy } -2-ethoxybenzoyl) -1,4:3, 6-dianhydro-D-glucitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -2-methoxybenzoyl ] oxy } -2-ethoxybenzoyl) -1,4:3, 6-dianhydro-D-glucitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -2-ethoxybenzoyl ] oxy } -2-methoxybenzoyl) -1,4:3, 6-dianhydro-D-glucitol;

2, 5-bis-O- (4- { [4- (acryloyloxy) -2-ethoxybenzoyl ] oxy } -3-methylbenzoyl) -1,4:3, 6-dianhydro-D-glucitol; and

2, 5-bis-O- (4- { [4- (acryloyloxy) -2-ethoxybenzoyl ] oxy } -3-methoxybenzoyl) -1,4:3, 6-dianhydro-D-glucitol.

As nematic compound A1 in the above-described procedure, the following further compounds can be employed, for example:

bis [4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) benzoic acid ] 2-methoxybenzene-1, 4-diester;

4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) -2-methylbenzoic acid 4- { [4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) benzoyl ] oxy } -2-methoxyphenyl ester;

bis [4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) -2-methyl-benzoic acid ] 2-methoxybenzene-1, 4-diester;

bis [4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) -2-methyl-benzoic acid ] 2-methylbenzene-1, 4-diester;

4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) -3-methoxybenzoic acid 4- { [4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) benzoyl ] oxy } -2-methylphenyl ester;

bis [4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) benzoic acid ] 2-methylbenzene-1, 4-diester;

bis [4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) -3-methoxy-benzoic acid ] 2-methylbenzene-1, 4-diester;

4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) -3, 5-dimethoxybenzoic acid 4- { [4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) -3-methoxybenzoyl ] oxy } -2-methylphenyl ester;

bis [4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) -3, 5-dimethoxy-benzoic acid ] 2-methylbenzene-1, 4-diester;

bis [4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) -3, 5-dimethoxybenzoic acid ] 2-methoxybenzene-1, 4-diester; and

4- { [4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) -3-methoxybenzoyl ] oxy } -2-methoxyphenyl 4- ({ [4- (acryloyloxy) butoxy ] carbonyl } oxy) -3, 5-dimethoxybenzoate.

As nematic compound A2 in the above-described procedure, the following further compounds can be employed, for example:

4- ({4- [4- (acryloyloxy) butoxy ] benzoyl } oxy) -3-methylphenyl 4- [4- (acryloyloxy) butoxy ] -2-methylbenzoate;

4- ({4- [4- (acryloyloxy) butoxy ] benzoyl } oxy) -3-methylphenyl 4- [4- (acryloyloxy) butoxy ] -3-methylbenzoate;

bis {4- [4- (acryloyloxy) butoxy ] -2-methylbenzoic acid } 2-methylbenzene-1, 4-diester;

4- ({4- [4- (acryloyloxy) butoxy ] -2-methylbenzoyl } oxy) -3-methylphenyl 4- [4- (acryloyloxy) butoxy ] -2, 5-dimethylbenzoic acid;

bis {4- [4- (acryloyloxy) butoxy ] -2, 5-dimethylbenzoic acid } 2-methylbenzene-1, 4-diester;

bis {4- [4- (acryloyloxy) butoxy ] benzoic acid } 2-methylbenzene-1, 4-diester;

4- ({4- [4- (acryloyloxy) butoxy ] -3, 5-dimethylbenzoyl } oxy) -3-methylphenyl 4- [4- (acryloyloxy) butoxy ] -2, 5-dimethylbenzoic acid;

bis {4- [4- (acryloyloxy) butoxy ] -3, 5-dimethylbenzoic acid } 2-methylbenzene-1, 4-diester;

bis {4- [4- (acryloyloxy) butoxy ] -3, 5-dimethylbenzoic acid } 2-methoxybenzene-1, 4-diester;

4- ({4- [4- (acryloyloxy) butoxy ] -3-methylbenzoyl } oxy) -2-methoxyphenyl 4- [4- (acryloyloxy) butoxy ] -3, 5-dimethylbenzoic acid;

bis {4- [4- (acryloyloxy) butoxy ] -3-methylbenzoic acid } 2-methoxybenzene-1, 4-diester;

4- ({4- [4- (acryloyloxy) butoxy ] benzoyl } oxy) -3-methoxyphenyl 4- [4- (acryloyloxy) -butoxy ] -3-methylbenzoate;

4- ({4- [4- (acryloyloxy) butoxy ] benzoyl } oxy) -3-methoxyphenyl 4- [4- (acryloyloxy) -butoxy ] -2, 5-dimethylbenzoic acid;

bis {4- [4- (acryloyloxy) butoxy ] -2-methoxybenzoic acid } 2-methoxybenzene-1, 4-diester;

bis {4- [4- (acryloyloxy) butoxy ] -3, 5-dimethoxybenzoic acid } 2-methoxybenzene-1, 4-diester;

bis {4- [4- (acryloyloxy) butoxy ] -3-methoxybenzoic acid } 2-methoxybenzene-1, 4-diester;

bis {4- [4- (acryloyloxy) butoxy ] benzoic acid } 2-ethoxybenzene-1, 4-diester;

bis {4- [4- (acryloyloxy) butoxy ] -2-methylbenzoic acid } 2-ethoxybenzene-1, 4-diester;

bis {4- [4- (acryloyloxy) butoxy ] benzoic acid }2- (prop-2-oxy) benzene-1, 4-diester;

4- ({4- [4- (acryloyloxy) butoxy ] benzoyl } oxy) -2- (prop-2-oxy) phenyl 4- [4- (acryloyloxy) butoxy ] -2-methylbenzoate;

bis {4- [4- (acryloyloxy) butoxy ] -2-methylbenzoic acid 2- (prop-2-oxy) benzene-1, 4-diester };

bis {4- [4- (acryloyloxy) butoxy ] -2, 5-dimethyl-benzoic acid 2- (prop-2-oxy) benzene-1, 4-diester };

bis {4- [4- (acryloyloxy) butoxy ] -3, 5-dimethyl-benzoic acid }2- (prop-2-oxy) benzene-1, 4-diester; and

bis {4- [4- (acryloyloxy) butoxy ] -3, 5-dimethoxy-benzoic acid }2- (prop-2-oxy) benzene-1, 4-diester.

It should be noted that the foregoing embodiments have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to illustrative specific examples, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein; rather, the invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.

Claims

1. A liquid crystal polymer marking obtainable by a process comprising the steps of:

(i) applying a first chiral liquid crystal precursor composition to a substrate;

(iii) applying a second chiral liquid crystal precursor composition to one or more regions of the applied first composition;

(v) the coated first and second compositions are subjected to at least one of a curing operation and a polymerization operation.

2. The marking of claim 1, wherein at least one of the first and second chiral liquid crystal precursor compositions comprises (i) one or more nematic compounds a and (ii) one or more chiral dopant compounds B capable of giving rise to a cholesteric liquid crystal state of the chiral liquid crystal precursor composition.

3. The marking of claim 1, wherein at least one of the first and second chiral liquid crystal precursor compositions comprises at least two compounds a.

4. The marking of claim 2, wherein at least one of the first and second chiral liquid crystal precursor compositions comprises at least two compounds a.

5. The marking of claim 2, wherein the one or more nematic compounds a and the one or more chiral dopant compounds B comprise a compound comprising at least one polymerizable group.

6. The marking of claim 4, wherein the one or more nematic compounds A and the one or more chiral dopant compounds B comprise a compound comprising at least one polymerizable group.

7. The marking of claim 5, wherein the at least one polymerizable group comprises an unsaturated carbon-carbon double bond.

8. The marking of claim 5, wherein the at least one polymerizable group comprises the general formula H₂C＝CH-C(O)-。

9. The marking of claim 7, wherein the at least one polymerizable group comprises the general formula H₂C＝CH-C(O)-。

10. The marking of claim 2, wherein the one or more nematic compounds a and the one or more chiral dopant compounds B all comprise at least one polymerizable group.

11. The marking of claim 3, wherein the one or more nematic compounds A and the one or more chiral dopant compounds B all comprise at least one polymerizable group.

12. The marking of claim 5, wherein the one or more nematic compounds A and the one or more chiral dopant compounds B all comprise at least one polymerizable group.

13. The marking of claim 7, wherein the one or more nematic compounds A and the one or more chiral dopant compounds B all comprise at least one polymerizable group.

14. The marking of claim 8, wherein the one or more nematic compounds a and the one or more chiral dopant compounds B all comprise at least one polymerizable group.

15. The marking of claim 2, wherein at least one of the first and second chiral liquid crystal precursor compositions comprises at least one chiral dopant compound B of general formula (I):

wherein: r₁、R₂、R₃、R₄、R₅、R₆、R₇And R₈Each independently represents C₁-C₆Alkyl or C₁-C₆An alkoxy group; a. the₁And A₂Each independently represents a group of formulae (i) to (iii):

(i)-[(CH₂)_y-O]_z-C(O)-CH＝CH₂；

(ii)-C(O)-D₁-O-[(CH₂)_y-O]Z-C(O)-CH＝CH₂；

(iii)-C(O)-D₂-O-[(CH₂)_y-O]_Z-C(O)-CH＝CH₂；

D₁represents a group of the formula:

D₂represents a group of the formula:

m, n, o, p, q, r, s and t each independently represent 0, 1 or 2;

y represents 0, 1, 2,3, 4, 5 or 6;

if y equals 0 then z equals 0, and if y equals 1 to 6 then z equals 1.

16. The marking of claim 3, wherein at least one of the first and second chiral liquid crystal precursor compositions comprises at least one chiral dopant compound B of the general formula (I):

(i)-[(CH₂)_y-O]_z-C(O)-CH＝CH₂；

(ii)-C(O)-D₁-O-[(CH₂)_y-O]Z-C(O)-CH＝CH₂；

(iii)-C(O)-D₂-O[(CH₂)_y-O]-C(O)-CH＝CH₂；

D₁represents a group of the formula:

D₂represents a group of the formula:

m, n, o, p, q, r, s and t each independently represent 0, 1 or 2;

y represents 0, 1, 2,3, 4, 5 or 6;

if y equals 0 then z equals 0, and if y equals 1 to 6 then z equals 1.

17. The marking of anyone of claims 1 to 16, wherein the first chiral liquid crystal precursor composition is the same as the second chiral liquid crystal precursor composition.

18. The marking of anyone of claims 1 to 16, wherein the second chiral liquid crystal precursor composition is different from the first chiral liquid crystal precursor composition.

19. The marking of anyone of claims 2 to 16, wherein the second chiral liquid crystal precursor composition differs from the first chiral liquid crystal precursor composition at least in that it comprises at least one of the one or more chiral dopant compounds B in a concentration different from the concentration of the same chiral dopant compound in the first chiral liquid crystal precursor composition.

20. The marking of anyone of claims 2 to 16, wherein the second chiral liquid crystal precursor composition differs from the first chiral liquid crystal precursor composition at least in that it comprises at least one chiral dopant compound B which is different from any of the one or more chiral dopant compounds B present in the first composition.

21. The marking of anyone of claims 1 to 16, wherein the second chiral liquid crystal precursor composition further comprises at least one of a pigment and a dye that absorbs in the visible or invisible region of the electromagnetic spectrum.

22. The marking of anyone of claims 1 to 16, wherein the second chiral liquid crystal precursor composition further comprises at least one of a luminescent pigment and a dye.

23. The marking of anyone of claims 1 to 16, wherein (ii) comprises heating the coated composition to a temperature of 55 ℃ to 150 ℃.

24. The marking of anyone of claims 1 to 16, wherein (iv) comprises heating at least one of the one or more regions to a temperature of 55 ℃ to 150 ℃.

25. The marking of anyone of claims 1 to 16, wherein (i) comprises applying the first chiral liquid crystal precursor composition by at least one of continuous ink jet printing, drop-on-demand ink jet printing, and spray coating.

26. The marking of anyone of claims 1 to 16, wherein (i) comprises applying the first chiral liquid crystal precursor composition by valve-jet printing.

27. The marking of anyone of claims 1 to 16, wherein (iii) comprises applying the second chiral liquid crystal precursor composition by at least one of continuous ink jet printing, drop-on-demand ink jet printing, and spraying.

28. The marking of anyone of claims 1 to 16, wherein (iii) comprises applying the second chiral liquid crystal precursor composition by valve-jet printing.

29. The marking of anyone of claims 1 to 16, wherein an air flow is passed through the one or more areas immediately after (iii).

30. The tag of any of claims 1-16, wherein the tag is in the form of at least one of: a picture, a logo, and a pattern presenting a code selected from one or more of a 1-dimensional barcode, a stacked 1-dimensional barcode, a 2-dimensional barcode, a 3-dimensional barcode, and an information matrix.

31. A marker as claimed in any one of claims 1 to 16, wherein the marker is in the form of a symbol.

32. The marking of anyone of claims 1 to 16, wherein the marking is in the form of an image.

33. A substrate comprising the marking of anyone of claims 1 to 32.

34. The substrate of claim 33, wherein the mark serves as at least one of a security element, an authenticity element, an identification element, and a tracking and tracing element.

35. The substrate of claim 33, wherein the substrate is at least one of an identity document, a label, packaging, a banknote, a security document, a stamp, an ink transfer film, and a reflective film.

36. The substrate of claim 35, wherein the substrate is a passport.

37. The substrate of claim 33, wherein the substrate comprises at least one of an identity document, a label, packaging, a banknote, a security document, a stamp, an ink transfer film, and a reflective film.

38. The substrate of claim 37, wherein the substrate is a passport.

39. A method of providing a substrate having a liquid crystal polymer marking, the method comprising:

40. A method as claimed in claim 39, characterized in that the method has the features defined in any one of claims 2 to 28.