[0001] This invention relates to secrecy protection in communicating written messages.
[0002] A typical application is in communicating codes (such as the code of a rechargeable
telephone card or of a credit card) or other messages written on a sheet, card etc.,
to a user by the organization providing the service.
[0003] In these and other similar cases it is important to be able to transmit a code (or
another message) secretly to the legitimate addressee such that this secrecy is protected,
in the sense that third parties are prevented from seeing the code, or if a third
party does violate the protection there remains an evident trace of the violation.
[0004] For this purpose it is known to cover the message with a layer of scratch-off ink,
ie an opaque ink adhering to the article and able to be scratched off the article
in small disintegrated particles by a sharp-edged hard object (a blade, a coin, etc.).
A typical widespread application is to protect the numbers on nationally distributed
lottery tickets of scratch card type.
[0005] In this example it is not possible to secretly know the protected numbers. They can
be known only by scratching the ink layer away, however this immediately reveals that
this action has been taken. This system hence effectively protects, in the aforesaid
sense, the secrecy of the message contained on the card. However it requires large
costly machinery, to be operated by an expert, hence limiting its application to very
large scale production.
[0006] Another known system uses self-adhesive labels with a transparent plastic laminar
surface which have their lower surface covered with permanently adhering glue and
their upper surface covered with a layer of scratch-off ink adhering to the support.
[0007] A label is applied to the message to be protected. Again in this case the ink layer
has to be scratched off to read the message, hence again revealing that this action
has been taken.
[0008] This system is simple and economical to apply. In particular, it requires the use
of devices (of the type suitable for applying self-adhesive labels to sheets and the
like) which are simple and are easy to use even by inexperienced personnel, and is
hence suitable for many different applications and usable by personnel without particular
expertise and without special machinery.
[0009] However such a system does not protect the message secrecy with total reliability
because it is possible to reduce the action of the glue, in particular by using hot
steam, and raise the self-adhesive label from the sheet to enable the secret message
to be read, after which the label can be repositioned, without leaving any sign that
this action has been taken.
[0010] An object of the invention is to provide a method, and the relative article carrying
the secret communication, which protects the message secrecy much more reliably than
the known system using self-adhesive labels with scratch-off ink, while at the same
time, in its preferred embodiment, requiring merely the application of a self-adhesive
label with scratch-off ink and the necessary application devices, which are relatively
very simple and easy to use.
[0011] This and further objects are attained by the invention as characterised in the claims.
[0012] The invention is described in detail hereinafter with the aid of the accompanying
figures, which illustrate one embodiment thereof by way of non-limiting example.
Figure 1 is a generic schematic enlarged cross-section through an article for the
secret communication of written messages, according to the invention.
Figure 2 is an exploded view of an article such as that of Figure 1, protected by
a usual envelope.
[0013] The reference numeral 10 indicates an article acting as a movable support for a written
message. This can be a sheet of cardboard, as in the illustrated example, or a sheet
of paper, plastic etc.
[0014] According to the invention, to the surface of the sheet 10 there is applied a lower
film of opaque ink (or equivalent covering material) adhering to the surface of the
article 10 and of the type which can be scratched off in the form of small disintegrated
particles by a hard sharp-edged object.
[0015] In a preferred (but not exclusive) embodiment, said lower ink film 21 is applied
to the support article 10 using a self-adhesive label 20 comprising a transparent
laminar plastic support 22 (in particular of polyester) having its lower surface covered
with a thin layer of permanently adhering glue 23 (also transparent), and having on
its upper surface said film of opaque ink 21, which is of scratch-off type and adheres
to the support 22.
[0016] Said label 20 is of known type, available commercially and known as a "self-adhesive
scratch-off label". Brand names of these labels include "ARCA ETICHETTE
R", "EUROLABEL
R" and "ETIKA
R".
[0017] At least one of these labels 20 is applied to the surface of the article 10, so that
a lower ink film 21 rigidly adheres to the article.
[0018] The secret message (for example a code) is then written on said lower ink film 21
so as to be visible on the ink film 21. The message is typically printed on the film
21 with an ink of different colour. The written parts of the message are shown schematically
in Figure 1, where they are indicated by 11.
[0019] Over the written message 11 there is then applied a transparent laminar plastic support
32, which carries on its upper surface an upper adhering film 31 of opaque ink (or
equivalent covering material) of the type able to be scratched off the plastic support
32 in small disintegrated particles by a hard sharp-edged object. The support 32 and
the relative film 31 are adheringly applied to said lower ink film 21 such as to cover
and hide the written message 11.
[0020] In a preferred (but not exclusive) embodiment, said upper ink film 31 is applied
to the lower film 21 using a self-adhesive label 30 comprising a transparent laminar
plastic support 32 (in particular of polyester) having its lower surface covered with
a thin layer of permanently adhering glue 33 (also transparent), and having on its
upper surface a film of opaque ink, which is of scratch-off type and adheres to the
support 32.
[0021] In particular, said label 30 is identical to the label 20.
[0022] In normal use, to read the message 11 it is sufficient (and necessary) to scratch
away the upper film 31 using a sharp-edged hard object such as a blade, a coin or
the like. In this manner the plastic upper support 32 is uncovered, and being transparent
enables the message lying below it to be seen. The support 32 itself is formed of
a material which is not substantially scratched by the object with which the film
31 is scratched off. In contrast, this latter is formed of a layer of covering material
(typically ink) which, while remaining adhering to the support 32 during normal handling,
easily crumbles when scratched, to uncover the support 32 and hence allow the underlying
message 11 to be seen.
[0023] At the same time, if a third person tries to lift the label 30 from the label 20
in an attempt to view the message 11 from the underside without scratching the layer
31 away, the upper plastic support 32 drags with it the lower ink film 21 adhering
to the adhesive layer 33, because the force of adhesion of the glue 33 is greater
than the force with which the ink 21 adheres to the lower support 22. Consequently,
in this case the ink forming the message 11 remains covered upperly by the upper ink
film 31 and lowerly by the lower ink film 21, and consequently it cannot be read.
If the lower film itself were to be scratched away, not only would obvious traces
of this action remain, but the actual message parts 11 would be also scratched away
together with the film 21, and hence the message 11 would be destroyed.
[0024] In conclusion, the message 11 can only be read by scratching off the upper ink layer
31, this having the required result of leaving a clear and unerasable indication of
the fact that this action has been accomplished.
[0025] Advantageously, the films of scratch-off ink 21 and 31 (or equivalent covering material)
are absolutely opaque to better conceal the message 11.
[0026] Figure 2 is an exploded view of an article, in particular a sheet of paper, cardboard
or plastic, for secret message communication, prepared by the aforedescribed method,
and in particular the article 10 shown in Figure 1.
[0027] The article 10 carries a lower self-adhesive label 20 which utilizing its self-adhesive
properties is applied to the surface of the sheet 10. The message (code) which is
to be kept secret is written on the upper surface of the label 20. An upper self-adhesive
label 30, in particular of greater length and width than the lower label 20, is applied
over the lower label 20 to totally cover this and also conceal its perimetral edge.
[0028] The sheet 10 formed in this manner is enclosed within an envelope composed of two
sheets, namely an upper sheet 41 and a lower sheet 42, which are joined together along
their respective perimetral edges 41' and 42'. The upper sheet 41 also possesses a
window 43 enabling the region carrying the secret message to be inspected.
[0029] The invention enables relatively very secure protection to be provided for the secret
message. In its preferred embodiment, this is achieved using and applying a (known)
self-adhesive label with scratch-off ink, requiring simple and inexpensive devices
(of the type suitable for applying a self-adhesive label to sheets and the like),
and hence suitable for many uses in various fields, it moreover being usable by users
without particular expertise and without special machines.
[0030] Numerous modifications of a practical and applicational nature can be made to the
invention, but without leaving the scope of the inventive idea as hereinafter claimed.
1. A method for protecting the secrecy of messages written on a movable support article,
in particular on a sheet of paper, cardboard or plastic, characterised by comprising
the following steps:
applying to the support article (10) a lower film (21) of opaque ink or equivalent
material adhering to the surface of the article (10) and of the type able to be scratched
off in small disintegrated particles by a sharp-edged hard object;
then writing the secret message (11) on said lower ink film (21), said writing being
such as to be able to be seen on said ink film (21);
then covering the written message with a transparent laminar plastic support (32),
which is applied adheringly to said lower opaque ink film (21) in such a manner as
to conceal the written message (11);
then adheringly applying to the upper surface of said plastic support (32) an upper
film (31) of opaque ink or equivalent material of the type able to be scratched off
the plastic support (32) in small disintegrated particles by a sharp-edged hard object.
2. A method as claimed in claim 1, characterised in that said upper film (31) of ink
(or equivalent covering material) is applied to said lower film (21) of ink (or equivalent
covering material) by applying at least one upper self-adhesive label (30) comprising
a transparent laminar plastic support (32) having its lower surface covered with permanently
adhering glue (33), and having on its upper surface said film (31) of opaque ink,
which is of scratch-off type and adheres to the support (32).
3. A method as claimed in claim 1, characterised in that said lower film (21) of ink
(or equivalent covering material) is applied to the support article (10) by applying
at least one lower self-adhesive label (20) comprising a transparent laminar plastic
support (22) having its lower surface covered with permanently adhering glue (23),
and having on its upper surface said film (21) of opaque ink, which is of scratch-off
type and adheres to the support (22).
4. A method as claimed in claim 1, characterised in that the films (21, 31) of opaque
ink (or equivalent material) of scratch-off type are absolutely opaque.
5. An article, in particular a sheet of paper, cardboard or plastic, for communicating
secret messages, characterised by comprising, to protect the message secrecy:
a lower film (21) of opaque ink (or equivalent covering material) adhering to the
surface of the article and of the type able to be scratched off the surface of the
article in small disintegrated particles by a sharp-edged hard object, the secret
message (11) being written on said lower ink film (21) and being such as to be visible
on said ink film (21);
a transparent laminar plastic support (32) adheringly applied to said lower opaque
ink film (21) in such a manner as to cover and conceal the written message (11);
an upper film (31) of opaque ink (or equivalent covering material) of the type able
to be scratched off in small disintegrated particles by a sharp-edged hard object,
and adheringly applied to the upper surface of said plastic support (32).
6. An article as claimed in claim 5, characterised by comprising a self-adhesive lower
label (20) comprising a transparent laminar plastic support (22) having its lower
surface covered with permanently adhering glue (23), and having on its upper surface
said film of opaque scratch-off ink adhering to the support, said self-adhesive lower
label (20) being adheringly applied to the surface of the article (10) and the message
(11) being written on its film of ink (21), and a self-adhesive upper label (30) comprising
a transparent laminar plastic support (32) having its lower surface covered with permanently
adhering glue (33), and having on its upper surface said film of opaque scratch-off
ink (31) adhering to the support.