Note: Descriptions are shown in the official language in which they were submitted.
' CA 02768601 2012-01-18
. .
,
Biluminescent colored fibers
Field of the invention
The invention relates to fluorescent colored fibers, which are marked with a
first
luminescent substance and which consist, at least to some extent, of an
adhesive, as
well as to a foil comprising colored fibers and to a document having the said
colored
fibers. The invention further concerns a process for manufacturing the
fluorescent
colored fibers, a process for manufacturing the foil with the fluorescent
colored fibers
as well as a process for manufacturing the document with the fluorescent
colored
fibers.
Prior art
Processes for manufacturing luminescent colored fibers are known from the
prior art as
well as processes for their introduction, in particular into papers, during
the
manufacture thereof.
A process is known from DE 41 33 977 Al for dyeing organic fibers, which
distinguishes itself from the prior art, spin dyeing, by dyeing small
quantities of fibers
using an aqueous solution of a cationic polymer and then with an aqueous
suspension
of a pigment. The particles used for dyeing should, wherever possible, have a
particle
size of < 10 pm.
A process is known from DE 37 19 48 A for manufacturing halo producing colored
fibers. These colored fibers stain upon drying the paper in which the colored
fibers are
embedded so that a halo is created around the colored fibers so that removal
of the
fibers can be noticed easily.
A safety paper with colored fibers is known from EP 1 268 935 B1 for which
various
luminescent colored fibers are embedded for the purpose of coding in various
subregions of the paper. The luminescent substances can be introduced into the
colored fibers or just applied over their surface. Luminescent properties are,
for
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CA 02768601 2012-01-18
A ,
,
example, the luminescent wave length or the decay time of the luminescent
radiation.
One disadvantage of this prior art is that the type of pattern, which is
introduced is very
limited. Just striped patterns are disclosed in EP 1 268 935 Bl. Furthermore,
the
process for manufacture of such a safety paper cannot be used for manufacture
of
plastic based documents since the colored fibers lie loosely on a firm plastic
surface
and would therefore be arbitrarily distributed and would no longer reproduce
the
applied pattern.
A safety paper is known from DE 103 24 630 Al with at least one type of
colored fibers
for manufacture of valuable documents made of safety paper, such as bank
notes. The
colored fibers contain luminescent substances with characteristic luminescence
properties. These colored fibers can be designed as bi-component fibers,
wherein a
core-sheath structure is formed. It is particularly advantageous if the sheath
is a low-
melting material and preferably melts in a temperature range of from 95 to 150
C.
These fibers demonstrate better adhesion in the substrate, wherein the colored
fibers
are added during manufacture of the paper. Manufacture of the colored fibers
can, for
example, take place using a melt spinning, wet spinning, or a dry spinning
process.
The colored fibers have a special geometric form and information can be coded
in this
geometric form. It is, however, disadvantageous that verification of such
fibers requires
technical aids and is time-consuming. For example, the form of the colored
fibers can
be viewed under an optical microscope. However, this process is not suitable
for rapid
verification, for example at a point of sale.
Problem according to the prior art and object of the invention
For colored fibers according to the prior art there is the problem that these
can be
easily replicated with the impression of a fluorescent color. To do this a
forger prints the
image of randomly distributed fibers on a counterfeit document using a dye.
Such
forgeries can be detected but only with some effort, for example with the aid
of a
microscope.
One further problem for colored fibers according to the prior art is
introduction into
plastic-based documents, in particular into documents, which have been
manufactured
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CA 02768601 2016-01-06
however, is that, in contrast to paper manufacture, the fibers do not have any
adhesion
to the foils for as long as these are not laminated. In this way one can
establish that a
large number of fibers are distributed by the production plants and can
therefore find
their way into other products, which should not contain any colored fibers or
should
contain different ones.
Based on this the object of the invention is to provide colored fibers, which
are easy
to verify, simple to apply, also structured, and which are also simple to
integrate, in
particular into plastic documents.
Description of the invention and preferred embodiments
These objects are fulfilled by fluorescent colored fibers, a foil comprising
colored
fibers, a document with fluorescent colored fibers, a process for manufacture
of
fluorescent colored fibers, a process for manufacture of a foil with
fluorescent colored
fibers, as well as a process for manufacture of a document with fluorescent
colored
fibers according to the present invention.
The above-mentioned objects are solved according to the invention in that the
colored
fibers contain at least two luminescent substances and an adhesive.
The fluorescent colored fibers according to the invention have a first and a
second
luminescent substance. The first luminescent substance emits a first
luminescent light
under first excitation conditions and the second luminescent substance emits a
second
luminescent light under second excitation conditions. The first and second
excitation
conditions in this arrangement are not identical and the first and second
luminescent
lights differ spectrally. Furthermore, the colored fibers at least partially
consist of an
adhesive.
One advantage of the fluorescent colored fibers according to the invention is
simpler
integration into plastic-based documents due to the adhesive and increased
security
against counterfeiting due to the distinguishable colors of the luminescent
light
emitted
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' CA 02768601 2012-01-18
One advantage of the fluorescent colored fibers according to the invention is
simpler
integration into plastic-based documents due to the adhesive and increased
security
against counterfeiting due to the distinguishable colors of the luminescent
light emitted
under the first and the second excitation conditions. Furthermore, the
adhesive leads to
an unbreakable connection between the colored fibers and the document so that
fluorescent colored fibers according to the invention cannot be removed out of
a
document and therefore a counterfeited document cannot be faked.
In one of the preferred embodiments of the colored fibers they have at least
one first
subregion and at least one second subregion. The subregions are arranged next
to
each other transverse to the direction of the fibers and preferably parallel
to each other.
For example, one subregion forms the left half and the other one the right
half of the
fiber, or one of the subregions encases the other subregion as, for example, a
core in a
cable is surrounded by insulation. The at least one first subregion consists
of an
adhesive. The at least one first subregion and/or the at least one second
subregion is
marked with the first luminescent substance and the at least one first
subregion and/or
the at least one second subregion is marked with the second luminescent
substance.
Two subregions have the advantage that it is possible to achieve spatial
separation of
the different luminescent regions, which are easy to verify optically. Both
luminescent
substances can therefore be present in the same and/or different subregions.
Here, and in the following text, the first subregions are understood as
regions, which
are preferably made of the same material but are spatially separated from each
other.
The same applies also for the second and possibly also the third and other
subregions.
Thus all of the first subregions preferably have same material properties,
which
differentiate these clearly from all second and other subregions. For example,
a colored
fiber made by spinning can consist of at least two fibers, which are separate
from each
other but are woven into each other. Yarns, which are made from the same
material
are seen as the same subregions, for example as the first subregions.
In a preferred embodiment of the colored fibers the first excitation
conditions for
excitation of the first luminescent substance comprise light with wave lengths
in a
range from 380 to 300 nm. The first luminescent substance can, in particular,
be
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' CA 02768601 2012-01-18
excited by UV-A and UV-B radiation, in particular with wave lengths of 365 nm
and
316 nm. Fora suitable selection of the materials or introduction of the
colored fibers
near to the surface it is also possible to have excitation by means of UV-C
radiation
with wave lengths up to 200 nm, in particular 254 nm.
In a further preferred embodiment of the colored fibers the second excitation
conditions
for excitation of the second luminescent substance comprise light with wave
lengths in
a range from 320 to 300 nm. The first luminescent substance can, in
particular, not be
excited by UV-A radiation but only with UV-B radiation, in particular not with
a wave
length of 365 nm but only that with 316 nm.
In a further preferred embodiment of the colored fibers the at least one first
subregion
encases the at least one second subregion as well as possibly also further
subregions.
For example, the at least one second subregion forms a core while the at least
one first
subregion surrounds this like a sheath as, for example, a line in a cable is
surrounded
by insulation.
In a further preferred embodiment of the colored fibers the at least one first
subregion
contains the first luminescent substance and the at least one second subregion
contains the second luminescent substance.
In a further preferred embodiment of the colored fibers the at least one first
subregion
contains the first luminescent substance and the at least one second subregion
contains the first and second luminescent substances.
In a further preferred embodiment of the colored fibers they furthermore have
at least
one third subregion, wherein the at least one second subregion and the at
least one
third subregion are encased by the at least one first subregion. In this
configuration the
at least one second and the at least one third subregion can be located next
to each
other or are adjacent to each other or are spaced apart from each other and
can be
separated from each other by the at least one first subregion.
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CA 02768601 2012-01-18
For example, the at least one second subregion and the at least one third
subregion
can be encased like two cores in a sheath made out of the at least one first
subregion,
comparable with a line with two cables. It therefore automatically arises that
also a
number of second and/or third as well as possibly also further subregions is
conceivable. If one designates the second subregions as A and the third
subregions as
B then, for example, the pattern ABA or the pattern ABAB can arise for the
single
strands in the colored fibers, wherein these three or four subregions are
overall
encased by one first subregion made out of an adhesive.
In a further preferred embodiment of the colored fibers the colored fibers or
the at least
one first subregion of the colored fibers consists of an adhesive. The
adhesive can be a
hot melt adhesive or a reactive adhesive. For example the hot melt adhesive
has a
softening point temperature of from 50 to 200 C, preferably from 80 to 120 C.
The
reactive adhesive is an acrylate adhesive for example. The adhesive preferably
is not
tacky at room temperature. In this way the colored fibers can be well
separated out
from each other during processing at room temperature.
In a further preferred embodiment of the colored fibers the luminescent
substances are
inorganic pigments. These luminescent substances can, in particular, be rare-
earth
doped oxides, oxinates, sulfides, oxysulf ides, phosphates, or vanadates. The
elements
europium, gadolinium, terbium, dysprosium, holmium, erbium, and thulium are in
particular used for rare-earth doping. One can mention, for example, the
possible
pigments of LUMILUX CD740 (red) and CD702 (green) from Honeywell. The most
advantageous pigments are those with a particle size of less than or equal to
10 pm,
preferably smaller than or equal to 8 pm and particularly preferred are those
smaller
than or equal to 6 pm. The inorganic pigments have a temperature stability,
which lies
above the softening point temperature of the polymer used.
In a further preferred embodiment of the colored fibers the at least one
second
subregion is made out of polyamide (PA) or a polyamide copolymer. One can, in
particular, use the polyamides PA12, PA6, and PA6.6. PA6 forms from ring
opening
polymerisation of c-caprolactam. PA6.6 (Nylon ) is manufactured from
hexamethylene
diamine and adipic acid through polycondensation with dehydration. It also
possible to
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' CA 02768601 2012-01-18
use polyethylene (PE), polyethylene terephthalate (PET), polyvinyl chloride
(PVC),
cellulose as well as their derivatives such as viscose or cellophane.
Polyamide is
preferred, however, since this material has the least interaction with the
usual laser
systems used in personalization of documents. The document material is, in
particular,
blackened as desired using a laser beam when using PA, also in the areas in
which
colored fibers are located.
The colored fibers can be selected to vary in their form and geometry.
Characterization
is usually based on the length, the diameter, and the cross-sectional form of
the
colored fiber. One typical length of a colored fiber lies in a range from 2 to
25 mm,
preferably about 6 mm. The diameter lies, for example, in a range from 20 to
150 pm
and preferably in a range from 50 to 60 pm. The cross-sectional form is
preferably
round (circular) or oval.
Furthermore the invention relates to a foil with fluorescent colored fibers
according to
the invention on the surface of which the colored fibers are fastened by means
of the
adhesive. The foil is preferably a plastic foil, which is preferably made out
of
polycarbonate (PC), in particular bisphenol-A polycarbonate, polyethylene
terephthalate (PET), their derivatives such as glycol modified PET (PETG),
polyethylene naphthalate (PEN), polyvinyl chloride (PVC), polyvinyl butyral
(PVB),
polymethyl methacrylate (PMMA), polyimide (PI), polyvinyl alcohol (PVA),
polystyrene
(PS), polyvinyl phenol (PVP), polypropylene (PP), polyethylene (PE),
thermoplastic
elastomers (TPE), in particular thermoplastic polyurethane (TPU),
acrylonitrile-
butadiene-styrene (ABS), Tesline as well as their derivatives. Furthermore,
the foils
can be co-extruded foils and other hybrid materials can be used, which also
include the
above-mentioned materials. The foils can also be made out of paper.
In a further preferred embodiment of the foil with the colored fibers, the
colored fibers
are arranged on the surface of the foil spatially structured. For example, the
colored
fibers are applied in the form of stripes on the foil so that stripe-shaped
areas form on
the foil in which there are colored fibers and stripe-shaped areas in which
there are no
colored fibers present. Furthermore, the areas in which there are colored
fibers present
can, for example, have the form of coats of arms, seals, or other patterns.
7
.' CA 02768601 2012-01-18
,
In a further preferred embodiment of the foil with the colored fibers there
are at least
two different types of fluorescent colored fibers fastened to the surface of
the foil.
In a further preferred embodiment of the foil with the colored fibers, the
different types
of colored fibers according to the invention are differently spatially
structured. For
example, the colored fibers are applied in the form of stripes on the foil so
that there
are first stripe-shaped areas on the foil in which a first type of colored
fibers is present
and there are second stripe-shaped areas on the foil in which a second type of
colored
fibers is present and third stripe-shaped areas in which there are no colored
fibers
present. Furthermore, it is possible to have areas, which have certain type of
colored
fibers, which, for example, can take the form of coats of arms or seals, while
the other
type is, for example, covering the whole surface.
Furthermore, the invention concerns a document with fluorescent colored fibers
according to the invention. This document is preferably a valuable or safety
document.
Examples of valuable or safety documents are a passport, identity card,
driving license,
visa, check and credit card, company identity card, credentials, member
identity card,
gift and purchase voucher, as well as a casino playing chip, bank note, check,
stamp,
and tax stamp. The document does, in particular, have a laminated card body.
Examples of documents with a laminated card body include a check and credit
card as
well as the German driving license.
The process according to the invention for manufacture of fluorescent colored
fibers
according to the invention comprises extrusion of at least a first polymer
through at
least one first spinneret while creating at least one first subregion of the
colored fibers
and optionally simultaneous extrusion of at least a second polymer through at
least one
second spinneret while creating at least one second subregion of the colored
fibers.
The at least one first polymer contains a first luminescent substance, which
emits a first
luminescent light under the first excitation conditions. An adhesive is
selected as a first
and/or as a second polymer. The first polymer and/or the second polymer
additionally
contains a second luminescent substance, which emits a second luminescent
light
under the second excitation conditions, wherein the first and second
excitation
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' CA 02768601 2012-01-18
conditions are not identical and the first and second luminescent lights
differ spectrally.
If only one first polymer is extruded then the first polymer contains the
first and the
second luminescent substance. If a first polymer and a second polymer are
extruded
then, for example, the first polymer can contain the first luminescent
substance and the
second polymer can contain the second luminescent substance or the first
polymer the
first luminescent substance and the second polymer the first and the second
luminescent substance.
In a further preferred embodiment of the process for manufacturing fluorescent
colored
fibers the at least one second subregion is encased by the at least one first
subregion.
This can, for example, be achieved by location of the spinnerets in a suitable
way,
which will be familiar to a specialist in the field. For example, six first
spinnerets can be
arranged around a second spinneret.
In a further preferred embodiment of the process according to the invention,
fluorescent
colored fibers are manufactured in a first step through extrusion of at least
one second
polymer through at least one spinneret while creating at least one second
subregion
and then, in a subsequent second step, a least one second subregion is encased
by at
least one first subregion of a first polymer. The first polymer in this case
is an adhesive.
The at least one second polymer contains a second luminescent substance, which
emits a second luminescent light under the second excitation conditions.
Furthermore,
the first polymer and/or the second polymer contains a first luminescent
substance,
which emits a first luminescent light under first excitation conditions,
wherein the first
and second excitation conditions are not identical and the first and second
luminescent
lights differ spectrally. For example, colored fibers can be manufactured
using a known
process in the first processing step. These are encased in a second step with
an
adhesive, which contains the first luminescent substance. The encasing can,
for
example, take place by means of dip coating.
The colored fibers manufactured according to one of the above-mentioned
processes
can, in a further step, be cut to any desired length in as far as this did not
already take
place during manufacture but that the colored fibers are manufactured instead
as
endless yarn. The length of a colored fiber is usually about 6 mm.
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. CA 02768601 2012-01-18
,
The process according to the invention for manufacturing a foil with
fluorescent colored
fibers comprises providing the foil, applying the fluorescent colored fibers
according to
the invention to the foil and fixing the fluorescent colored fibers to the
foil.
In a preferred embodiment of the process for manufacturing the foil the
colored fibers
are fixed in place using heat and/or UV radiation. For example the foil is
passed under
an IR emitter or through a roller laminator after applying the fluorescent
colored fibers
so that the adhesive of the colored fibers softens or becomes liquid and
therefore the
colored fibers are fixed to the foil. The foil can alternatively be put in an
oven after
applying the fluorescent colored fibers, which heats the foil up to a
temperature, which
is above the softening point temperature of the adhesive but below the
softening point
temperature of the foil. Alternatively or additionally the foil can be passed
under a UV
emitter after applying the colored fibers in order to activate the reactive
adhesive of the
colored fibers and thus to achieve fixing of the colored fibers to the foil.
In a further preferred embodiment of the process for manufacturing the foil
the colored
fibers are only applied to at least one first subarea of the foil. For example
the colored
fibers are applied in a stripe formation to the foil. This can take place, for
example, by
spraying on, spreading on or pressing on. The colored fibers can also, for
example, be
applied in the form of coats of arms or seals. This can take place through
stamping on
or imprinting.
In a further preferred embodiment of the process for manufacturing the foil
which is
alternative to the previously described embodiment, the colored fibers are
applied to
the whole surface of the foil. The colored fibers are, however, only fixed to
at least one
first subarea of the foil. This occurs, for example, through locally varying
radiation with
IR or UV light so that only colored fibers in the at least one first subarea
of the foil are
fixed in place. The colored fibers, which were not fixed in place are
subsequently
removed from the foil, for example by turning over the foil or by blowing off
or
suctioning off the colored fibers, which are not fixed in place.
CA 02768601 2016-01-06
fluorescent substance so that this difference can only be observed in a
specially
equipped laboratory.
In a further preferred embodiment of the process for manufacturing the foil
the at least
one first subarea and at least one subarea create a pattern. Examples of such
patterns
are coats of arms on a substrate, wherein the coat of arms consists of first
subareas
with a first color and the substrate consists of second subareas with a second
color.
One further example of a pattern is the value number on a bank note. The at
least one
second subarea can comprise the at least one first subarea or surround it or
the other
way round. The at least one first and at least one second subareas are not
identical
however. This is, for example, the case if the first subarea comprises the
whole surface
of the foil and the at least one second subarea only one part of the surface,
for
example in the form of a coat of arms. For example, the first subareas can be
a subset
of the second subareas so that the coat of arms is made up of a mixture of the
first and
the second colors on a substrate of the second color.
The process according to the invention for manufacturing a document with
fluorescent
colored fibers comprises bringing together of at least one foil with colored
fibers
according to the invention as well as, if necessary, at least one further foil
and
lamination of the combined foils.
In a preferred embodiment of the process for manufacturing the document at
least one
document will be cut out or stamped out of the laminate after lamination. This
is
particularly preferred if the laminate is a multiple use one. At least two
documents
(uses) can be created individually out of a multiple use laminate, for example
cut out
or stamped out.
In yet another aspect, the present invention provides a foil with fluorescent
colored
fibers, wherein the colored fibers are marked with a first luminescent
substance,
wherein the first luminescent substance emits a first luminescent light under
first
excitation conditions and wherein the colored fibers at least partially
consist of an
adhesive, wherein the colored fibers are marked with a second luminescent
substance,
the second luminescent substance emits a second luminescent light under second
excitation conditions, the first and second excitation conditions are not
identical, and
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CA 02768601 2016-01-06
the first and second luminescent lights differ spectrally and wherein the
colored fibers
are fastened by means of the adhesive to the surface of the foil, wherein the
foil is a
plastic foil, wherein the colored fibers are randomly distributed on the foil,
wherein
the colored fibers have at least one first subregion and at least one second
subregion,
wherein the subregions are arranged next to each other transverse to the
direction of
the fibers, wherein the at least one first subregion consists of the adhesive,
wherein
the at least one first subregion is marked with the first luminescent
substance, and
wherein the at least one second subregion is marked with the second
luminescent
substance.
In yet another aspect, the present invention provides a process for
manufacturing a
foil with fluorescent colored fibers comprising the following steps: a)
providing the
foil wherein the foil is a plastic foil, b) applying the fluorescent colored
fibers in a
random pattern onto the foil, wherein the colored fibers are marked with a
first and
second luminescent substance, wherein the first luminescent substance emits a
first
luminescent light under first excitation conditions, wherein the second
luminescent
substance emits a second luminescent light under second excitation conditions,
wherein the first and the second excitation conditions are not identical,
wherein the
first and second luminescent lights differ spectrally, wherein the colored
fibers at least
partially consist of an adhesive, and wherein the colored fibers have at least
one first
subregion and at least one second subregion, wherein the subregions are
arranged next
to each other transverse to the direction of the fibers, wherein the at least
one first
subregion consists of the adhesive, wherein the at least one first subregion
is marked
with the first luminescent substance, and wherein the at least one second
subregion is
marked with the second luminescent substance, and c) fixing the fluorescent
colored
fibers by means of the adhesive onto the surface of the foil.
Exemplified embodiments of the invention are now described with reference to
the
appended figures. The individual figures show:
Fig. 1 a to g: colored fibers in a schematic illustration in a cross-sectional
view;
Fig. 2: a colored fiber in a schematic illustration in a view from
above;
1 1 a
CA 02768601 2016-01-06
Fig. 3:
manufacture of a foil with colored fibers in a schematic illustration in a
cross-sectional view;
lib
,
, CA 02768601 2012-01-18
In a preferred embodiment of the process for manufacturing the document at
least one
document will be cut out or stamped out of the laminate after lamination. This
is
particularly preferred if the laminate is a multiple use one. At least two
documents
(uses) can be created individually out of a multiple use laminate, for example
cut out or
stamped out.
Exemplified embodiments of the invention are now described with reference to
the
appended figures. The individual figures show:
Fig. 1 a tog: colored fibers in a schematic illustration in a cross-
sectional view;
Fig. 2: a colored fiber in a schematic illustration in a view from
above;
Fig. 3: manufacture of a foil with colored fibers in a schematic
illustration in a
cross-sectional view;
Fig. 4: manufacture of a document with colored fibers in a
schematic
illustration in a cross-sectional view;
Fig. 5: a document with colored fibers in a schematic illustration
in a view
from above;
Fig. 6: a further document with colored fibers in a schematic
illustration in a
view from above;
Fig. 7: a further method of manufacture of a foil with colored fibers
attached
thereon in a schematic illustration in a cross-sectional view.
The same reference numbers used below refer to the same elements.
Fig. 1 shows a schematic illustration of colored fibers in a cross-sectional
view. The
sizes are not shown true to scale but are just to clearly indicate the spatial
arrangement
relative to each other.
Fig. la shows a cross-section of a colored fiber 10, which consists
exclusively of one
first subregion 11. The first subregion consists of an adhesive. The adhesive
contains a
first and optionally also a second luminescent substance so that the colored
fiber 10
emits another luminescent light under the first excitation conditions than
under the
second excitation conditions. The advantage of the colored fiber 10 shown is
simple
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' CA 02768601 2012-01-18
manufacture in one processing step. Since both luminescent substances are,
however,
not spatially separate from each other replication is relatively simple.
Fig. lb shows a further colored fiber 10.1, which consists of a first
subregion 11.1 and
a second subregion 12.1. The first subregion 11.1 consists of an adhesive and
encases
the second subregion 12.1. For example the adhesive is a hot melt adhesive and
the
second subregion consists of polyamide. As an example, a first luminescent
substance
is contained in the first subregion 11.1 and optionally a second luminescent
substance
is contained in the second subregion 12.1. One advantage of this embodiment is
simplified optical recognition due to the very different intensity profile and
the different
spectral characteristic of the first and second luminescent lights. It is
furthermore
advantageous that, due to the different properties of the materials, removal
of a colored
fiber 10.1 from a document without destroying it is no longer possible since
the
adhesive of the subregion 11.1 can create a permanent bond to the document.
Fig. lc shows a further colored fiber 10.2, which consists of a first
subregion 11.2, a
second subregion 12.2 and a third subregion 13.2. For example, a first
luminescent
substance can be contained in the second subregion 12.2 and a second
luminescent
substance in the third subregion 13.2. In this embodiment the thickness of the
first
subregion 11.2, which consists of the adhesive can be very thin since this
simply needs
to provide the adhesion between the colored fiber and the foil.
Fig. ld shows a further colored fiber 10.3, which consists of a first
subregion 11.3, a
second subregion 12.3, and a third subregion 13.3. The structure of this
colored fiber is
the same as that of the colored fiber from Fig. 1 c, wherein the second
subregion 12.3
and the third subregion 13.3 are separated by the first subregion 11.3. One
such
colored fiber can, for example, be created by the connection between two
colored
fibers according to prior art by means of an adhesive, which creates the first
subregion
11.3.
Fig. le shows a further colored fiber 10.4, which consists of a first
subregion 11.4, a
second subregion 12.4, a third subregion 13.4, and a fourth subregion 14.4. As
an
example, the second subregion can contain a first luminescent substance, the
third
13
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CA 02768601 2012-01-18
,
subregion a second luminescent substance, and the fourth subregion a third
luminescent substance. The first subregion consists of an adhesive, which can
fix the
colored fiber to a foil. One advantage of this colored fiber is presentation
of three
different colors lying next to each other, which leads to simple optical
recognition. It is
furthermore possible with three colors to already be in a position to
represent the
majority of national colors so that, for example, country-specific coding may
be
performed.
One special case here is a colored fiber with a first subregion 11.4, two
second
subregions 12.4 and 14.4, and a third subregion 13.4. For example, the two
second
subregions contain a first luminescent substance and the third subregion a
second
luminescent substance. The first subregion 11.4 consists of an adhesive.
Fig. if shows such a further colored fiber 10.5. This has a first subregion
11.5
consisting of an adhesive and two second subregions 12.5. For example the
first
subregion 11.5 contains a first luminescent substance and the second
subregions a
second luminescent substance. One advantage of this embodiment with a number
of
second subregions is that the breaks in the strands, which occur during
manufacture of
the colored fibers in the second subregions will, without difficulty, not be
optically be
perceived as a fault. This reduces the number of rejects.
Fig. 1d shows a further colored fiber 10.6, which consists of a first
subregion 11.6,
consisting of an adhesive, as well as two second subregions 12.6 and two third
subregions 13.6. This form represents a combination of the colored fibers
shown in Fig.
1d and Fig. If, which combines the advantages of simple and secure
verification and
low reject rate manufacture.
Fig. 2 shows a colored fiber 10.2 according to Fig. 1c shown in a view from
above. This
has a first subregion 11.2, which consists of adhesive. The colored fiber
furthermore
has a second subregion 12.2, which contains a first luminescent substance as
well as a
third subregion 13.2, which contains a second luminescent substance. For
optical
verification of the colored fibers this produces the image of two luminescent
stripes
14
, CA 02768601 2012-01-18
lying next to each other of different colors. The typical length of such a
colored fiber is
an average of about 6 mm.
Fig. 3 is a schematic representation of manufacture of a foil with the colored
fibers
according to the invention shown in a cross-sectional view. A foil 30 is made
available
in the first step (a). The foil 30 can, for example, be made out of PC. The
colored fibers
(step b) are then applied to the foil, which has, for example, a first
subregion 31 and a
second subregion 32. The first subregion 31 consists of a hot melt adhesive,
which is
not tacky at room temperature. In this way the colored fibers can be separated
out from
each other and processed. The first subregion 31 preferably contains a first
luminescent substance and the second subregion 32 a second luminescent
substance.
In a subsequent step (c) the colored fibers are fixed in place, for example
through
warming using an IR lamp, which brings the first subregion 31 up to a
temperature at
which the hot melt adhesive softens. In this way a fixed bond is achieved
between the
colored fibers and the foil 30. It is schematically shown here that
deformation of the first
subregion 31 can occur because of this. This can be advantageous to improve
the
adhesion of the colored fibers onto the foil 30.
Fig. 4 is a schematic representation of manufacture of a document according to
the
invention with colored fibers according to the invention shown in a cross-
sectional view.
In a first step (a) a foil 30 according to the invention with colored fibers,
which have a
first subregion 31 and a second subregion 32, which are fixed to the foil 30
brought
together in stack with further foils, here for example two foils 35 and 36.
Normal
structures of plastic-based documents will be known to the specialist in the
field,
wherein there are usually 3 to 15 foils used. For example foils 30, 35, 36 are
PC foils,
which have a glass transition temperature of about 148 C. These are laminated
under
increased pressure and increased temperature, usually 170 to 210 C, for 5 to
60 minutes (step b). A monolithic card body 38 is created. The colored fibers
are inside
the monolithic card body 38, wherein the first subregion 31, which consists of
a hot
melt adhesive, is deformed and has been bound to the document since the
adhesive
has a glass transition temperature or a melting point below the glass
transition
temperature of PC and in particular below the lamination temperature. The
second
subregions can preferably be designed in such a way that their geometrical
form does
CA 02768601 2012-01-18
not or does not appear to change under lamination conditions. The first
subregion 31
advantageously contains a first luminescent substance and the second subregion
32 a
second luminescent substance. The first subregion will no longer be detected
as clearly
delimited area during verification since it is spread into the document during
lamination.
The colored fiber can no longer be totally removed anymore through deformation
of the
first subregion 31 but just the second subregion 32 so any attempt at
manipulation is
very obvious.
For the specialist in the field it is clearly apparent that foil 35 could, for
example, be a
hologram, for example a volume hologram or a kinegram. Furthermore, foil 36
can be a
so-called inlay, which has a chip and an antenna for contactless
communication. Such
an inlay can consist of a thermoplastic elastomer, in particular thermoplastic
polyurethane (TPU), or a TPU-PC composite. The specialist in the field will
also know
that an adhesive can be introduced to reduce the lamination temperature
between the
foil 30 and the foil 35 and/or the foil 30 and the foil 36.
Fig. 5 shows a document 40 with colored fibers 42 according to the invention
in a top
view. The colored fibers are on the subareas 41 of the document 40. The
subareas are,
for example, arranged in the form of stripes. The stripe-shaped subareas can,
for
example, represent a code, for example a bar code. This code does, for
example, code
the value of document 40, for example a bank note. Other forms are conceivable
instead of a stripe-shaped arrangement, in particular a series of letters
and/or numbers,
for example a value number or a country code.
Fig. 6 shows a further document 50 with colored fibers according to the
invention 53,
54 in a top view. The colored fibers 53 are located on a first subarea 51 of
the
document 50 and the colored fibers 54 are located on a second subarea 52 of
the
document 50. In the case shown the second subarea 52 comprises the whole
surface
of the document. The colored fibers 53 differ in the case shown from colored
fibers 54
in their length. For example, the colored fibers 53 are about 5 mm long while
the
colored fibers 54 are about 20 mm. The colored fibers can also be
differentiated
between by or instead of the length, for example, based on the luminescence
color
effect. The first subarea 51 is shown here as circular. It is, however, easy
to conceive
16
' CA 02768601 2012-01-18
that the first subarea 51 takes on the form of a coat of arms or a seal, a
symbol, for
example an eagle, or a value number. It is furthermore simple to recognize
that a
number of first subareas could together represent a coat of arms or a seal, a
symbol,
for example an eagle, or a value number, in particular a multi-digit value
number.
Fig. 7 is a schematic representation of manufacture of a further foil with
colored fibers
fixed to it, shown in a cross-sectional view. A foil 30 is made available in
the first step
(a). The foil 30 can, for example, be made out of PC. Colored fibers (step b)
are then
applied, which have, for example, a first subregion 31 and a second subregion
32. The
first subregion 31 consists of a hot melt adhesive, which is not tacky at room
temperature. In this way the colored fibers can be separated out from each
other and
processed. The first subregion 31 preferably contains a first luminescent
substance
and the second subregion 32 a second luminescent substance. Application does
not
take place structured, in particular across the whole surface. In a following
step (c) the
colored fibers are fixed onto the foil in certain prescribed subareas, that is
the fixing
takes place structured, so that the colored fibers are only connected with the
foil 30 in
the subareas in which they should be applied to the foil 30. The colored
fibers are, for
example, fixed to the foil by heating with an IR lamp, which heats the first
subregion 31
to a temperature at which the hot melt adhesive softens. In this way a fixed
bond is
achieved between the colored fibers and the foil 30. In the figure it is
schematically
shown that deformation of the first subregion 31 can occur because of this.
This can be
advantageous to improve the adhesion of the colored fibers onto the foil 30.
In a final
step (d) the non-fixed colored fibers are removed, for example by blowing off
or
suctioning off.
17
