[0001] The invention relates to a display card for numerical information with at least
a base surface of background colour and at the front thereof, in mirror image, one
or more numerical markings consisting of seven segments of another colour which markings
each essentially have the form of an eight. Such a display card is known from the
US Patent 4,539,768.
[0002] These known cards or boards are provided with covering elements which can be swivelled
or folded aside for each of the said segments of the numerical markings. Each number
from 0 to 9 can be derived from each of these numbers in the form of an eight. In
accordance with the numerical information, which the user of said display cards or
boards wishes to display at the time, he will fold in or insert manually particular
covering elements in each case and as a result display the required numbers. To change
the numerical information, he will again fold aside the first mentioned covering elements
and fold in others. This is a relatively cumbersome and time-consuming process in
which the pivotable covering elements are subjected to wear and the service life of
the entire structure is limited as a result. Usually locking elements are also necessary
in this case in order to lock the covering elements in a position once it has been
taken up.
[0003] The object of the invention is to eliminate the abovementioned problems and to provide
a display card for numerical information which is extremely practical and durable
and with which the numerical information can be indicated and altered very rapidly
by a particularly simple operation.
[0004] According to the invention, this is achieved in a display card of the type mentioned
in the introduction in that a layer of clear transparent material, which can be written
on, is situated at the front on top of the numerical markings and the base surface
so that any desired number can be displayed by covering particular segments by means
of ink of the background colour, the ink being of a composition which is readily removable
so that any numerical display can be altered.
[0005] In this embodiment, a back surface of yet another colour may be provided at the back
over the base surface and, if necessary, projecting therefrom.
[0006] In a further embodiment, alongside the base surface with numerical markings, other
surfaces with text and/or symbols are provided between the back surface and the layer
which can be written on.
[0007] The invention will be explained in more detail. Reference is made to the drawings
in which Figure 1a, b and Figure 2a, b, c give front views of a display card or display
board such as a currency, interest and price indicator.
[0008] For the layer of clear transparent material at the front which can be written on
use can advantageously be made of PVC which has high chemical resistance and is readily
printed on and mechanically machined. Any other clear and transparent plastic may
also be used.
[0009] The base surface of background colour and the numerical markings of an other colour
are usually provided by means of screen printing. In this case, the numerical markings
in the other colour are provided at the back of the PVC layer by means of special
screen printing ink. Said numerical markings which consist of seven segments and which
each form the figure 8 are provided in mirror image on the PVC layer as a diapositive.
The number of figures, the size and the colour is unlimited. Usually said figures
are white and the base surface, which forms the background of said figures, is black.
[0010] After the numerical markings have been provided, the base surface with the background
colour are provided in a single printing operation. If necessary, in addition to
the base surface, still more texts and/or symbols are then provided in a subsequent
printing operation on the PVC layer. Thus, other information may also be displayed
on such a display card such as texts, currencies, product descriptions etc., etc.
The number of colours is unlimited and it is possible to change over from simple line/tint
surfaces to four-colour lithos.
[0011] After all the colours have been printed, a fixing ink, the colour of which is usually
white, is printed as the back surface in a final printing operation. Other colours
are, however, also possible. In some cases it is possible to fix the printing inks
with a self-adhesive plastic film. Although the colour of this is also usually white,
other colours are possible. If desired, a magnetic film can be provided by means of
a glue layer. As a result said display card can be bonded to, or hung onto, a magnetic
board.
[0012] The embodiment can also be such that the base surface or the numerical image carrier
is provided by offset printing on paper, front and back being sealed by enclosure
in a layer of clear material such as PVC. As a result of this a laminated display
card which is constructed as a single entity and is resistant to moisture and dirt
is produced.
[0013] Because the PVC layer at the front can satisfactorily be written on and erased,
particular segments can be covered with a felt pen permanently attached or with a
so-called board marker with the ink emerging therefrom which has the same colour as
the background colour of the base surface so that any desired numerical combination
can be displayed. In the case of the felt pen, the ink can be removed with a cloth
or wad of cotton wool and a solvent/remover. The composition of said solvent/remover
is such that all the residues of the felt pen ink are removed. The PVC layer and the
final fixing layer are not sensitive to it. In the case of the board marker, the pen
ink can be removed with a small cloth.
[0014] For the uniformity of display it is of importance that, after segments have been
covered, the optical result is uniform regardless of the person who has carried out
the particular covering operation with felt pen or board marker. This applies obviously
both to vertically situated numbers and obliquely situated numbers.
[0015] Optional lines or squares in the back surface may be helpful in writing in a straight
manner and rhythmically on said display card.
[0016] Said display card can be used with extraordinary advantage in retail and wholesale
trade for the pricing or offering of articles for which the numerical information
has to be altered regularly. As a result of this it is not necessary to produce always
a new card. Furthermore, said display card or board can be used as a currency or
interest indicator in banks and border exchange bureaus in which the currency indications
have to be modified regularly.
[0017] Said display card can also be used for lists of food and drinks, and prices in restaurants,
hotels, conference centres, theatres and the like. Said display card can also be used
as an indicator or as a publication board, inter alia, for time indication.
1. Display card for numerical information with at least a base surface of background
colour and at the front thereof, in mirror image, one or more numerical markings consisting
of seven segments of another colour which markings each essentially have the form
of an eight, characterized in that a layer of clear transparent material which can
be written on, extends at the front on top of the numerical markings and the base
surface so that any desired number can be displayed by covering particular segments
of the numerical markings by means of ink of the background colour, the ink being
of a composition which is removable so that any numerical display can be altered.
2. Display card according to claim 1, characterized in that a back surface of yet
another colour is provided at the back over the base surface and, if necessary, projecting
therefrom.
3. Display card according to claim 2, characterized in that, alongside the base surface
with numerical markings, other surfaces with text and/or symbols are provided between
the back surface and the layer which can be written on.
4. Display card according to claim 3, characterized in that the base surface, the
numerical markings, the back surface, the other surfaces with text and/or symbols
consist of screen printing inks which are provided in different printing operations.
5. Display card according to claim 4, characterized in that the back surface is a
fixing ink.
6. Display card according to claim 4, characterized in that the back surface is a
self-adhesive plastic film.
7. Display card according to one of the claims 2 to 6, characterized in that a magnetic
film is provided at the back over the back surface.
8. Display card according to claim 2, characterized in that the layer of transparent
material which can be written on is of PVC.
9. Display card according to claim 1, characterized in that the background colour
of the base surface is black and that the other colour of the numerical markings is
white.
10. Display card according to claim 1, characterized in that the numerical markings
are upright.
11. Display card according to claim 1, characterized in that the numerical markings
are oblique.
12. Display card according to claim 1, characterized in that the ink can be applied
with a felt pen.
13. Display card according to claim 1, characterized in that the ink can be applied
with a board marker.