DE19537177C2 - Process for producing a plastic card in the form of an identification card, telephone card, credit card, health insurance card or the like - Google Patents

Description

The invention initially relates generally to a method of manufacture plastic cards in the form of an identity card, telephone card, Bank card, credit card, health insurance card or the like Such cards are used on a large scale.

However, blind and severely visually impaired people have the problem that they don't have the many different cards can distinguish.

The same problem occurs when distinguishing banknotes on. For this reason points in the Federal Republic of Germany every note has a tactile characteristic, the one Differentiation of different banknotes should enable. Unfortunately, the tactile features are already easy Most blind people no longer have "crumpled" banknotes palpable. However, since each banknote has a different length the blind distinguish the banknotes with one specially designed length measuring device and sort them like this then identified the banknotes in her wallet a.

A distinction between the different cards (telephone cards, Health insurance cards, bank cards, credit cards or the like) according to the geometrical dimensions, as with banknotes not possible here because the format of the cards is standardized. This format has the name ID-1 and is in ISO 7810 fixed.

Blind people are able to use chip cards from non-chip cards on the basis of the chip module with its metallic contact surfaces to distinguish a distinction from different ones However, chip cards are not possible. However, since the  Most cards are now chip cards, is the chip module unsuitable as a distinguishing criterion.

Many cards, especially credit cards, are for display of cardholder-related data, where this data from the back of the card to the front of the card be embossed in relief. Such embossing will used to process the cardholder-related data using a Impression process z. B. to transfer to a payment receipt. This is done with special devices, so-called imprinters. Such embossing is e.g. B. in DE 37 31 853 A1 described. The embossing described there is in two Levels formed, with in the first stage using a A plateau is mechanically stamped into the card and in the second stage on this plateau by means of Laser radiation with the relief structure cardholder-related data is generated. The embossed However, alphanumeric characters are not for the blind identifiable.

Because the cards are indistinguishable, blind people keep currently their cards in separate sleeves, which then be individually labeled to identify the to ensure that the card is inserted. However, this is very cumbersome and error-prone because the cards are very light can be sorted incorrectly, so that again strangers Help must be sought.

To remedy this, DE 295 12 254 U1 Plastic card for the visually impaired and blind with one tactile user information in Braille (Braille) suggested. To make this card is there suggested that the Braille script be stamped, embossed, is glued or printed on. The punching and embossing processes have the disadvantage that the respective Back of card is injured, causing for example one there arranged magnetic strip would be destroyed. Another  The disadvantage is that the processes are not particularly flexible, since changes in Braille always change the Punching or embossing tools require. The adhesive and Printing processes have the disadvantage that the raised Braille dots with mechanical Can release loads from the card body; u. U. can Braille dots thus suddenly produced "jump off". In addition, the gluing and printing processes require additional and time-consuming curing of the adhesive or the ink.

It is therefore the object of the invention to provide a method with which it is possible to create braille Plastic cards without the disadvantages described above to apply.

This task is characterized by the characteristics of the Claim 1 solved. The subsequent ones Sub-claims (claims 2 to 9) represent advantageous and beneficial Embodiments of the invention. The claims 10 and  11 relate to plastic cards for use in the inventive method.

The invention is based on the idea of palpable on cards produced by the method according to the invention, raised alphanumeric information in the form of Braille To develop writing by using Braille Points by applying the plastic card locally Laser radiation are formed. The circumstance exploited that the plastic material of the cards due the interaction with the intense laser radiation locally "foams", resulting in a limited curvature of the Map surface leads. The macroscopically called "foaming" too observing effect is through the following processes causes: change or destruction of the polymer structure, Oxidation processes, formation of microscopic Soot particles, release of gases etc. The individual processes are naturally strongly dependent on the type of used  Plastic material, the laser wavelength and the intensity and the duration of the laser irradiation.

The laser braille is very easy to feel for the blind. It has shown that Braille dots already with a Height of 100 µm are easy and safe to feel. To this The most diverse cards can be combined in one way Identify blind familiar ways. So z. B. a Card type name, such as B. "Health Insurance Card", "Bank card", "credit card", "telephone card", "train card" or the like can be applied to the card as laser braille. This way blind people can identify the cards and differentiate. Dealing with the different cards, from those who will be given more and more will become blind and strong visually impaired hereby relieved, whereby Uncertainties are eliminated.

The process of laser braille labeling can be found in easier and cheaper way into the existing Integrate manufacturing processes for cards.

Health insurance cards, bank cards, credit cards show already a laser inscription for display user-related data, i.e. H. go through these cards within their manufacturing process Laser marking machine. This manufacturing step is part of the so-called card personalization. To manufacture the laser Braille is not a change in equipment Laser marking machine necessary. It’s enough Control of the computer-aided laser marking system for the generation of easily palpable Braille dots expand. Because of the high processing speed is such a computer-controlled laser marking system the time required to generate Braille Plastic cards very low. Another advantage is that Flexibility of a laser marking system with regard to the Design and positioning of Braille on the Map surface.  

Since the above-described - that is to say produced by the method according to the invention - cards, in contrast to z. B. circulating banknotes, owner-specific, it is not necessary on all cards - including the cards for Non-visually impaired - to apply laser braille. Since the laser braille with a very small raised height is palpable, there are no complications when printing embossing used as a printing block, which may also be present on the card.

One advantage of laser braille over means Embossing matrices embossed Braille characters is that at Generation of the laser braille on the respective back is not "hurt". Thus, it is e.g. B. possible the laser Braille on the one arranged on the map Apply magnetic stripe opposite side. Another Advantage of laser braille over means Embossing dies embossed Braille dots is the one above mentioned flexibility of the laser marking system and the The fact that no additional workpiece and no separate Work place within the card production is needed.

The relatively flat laser braille at the same time undamaged back side affects the card guide and the Card transport in card readers in no way.

On the basis of the accompanying drawings, the invention is intended are explained in more detail below. It shows:

Fig. 1 to Fig. 3 are plan views of cards with laser Braille,

Fig. 4 is a plan view of a card with marking of the normalized location areas for the chip module and the high-embossing,

Fig. 5 is a plan view of the back of the card of Fig. 4 with the normalized layer portion of the magnetic stripe,

Fig. 6 is a schematic representation of a laser marking machine for generating the laser Braille on plastic cards,

Fig. 7, the local intensity profile of the laser write spot on the card surface,

Fig. 8 shows the intensity distribution of two only slightly overlapping laser writing spots,

Figure 9 shows the intensity distribution of two strongly overlapping laser writing spots.,

Fig. 10 to Fig. 12 sections through differently configured laser Braille points,

Laser beam guidance variants illustrated schematically by Fig. 15 Fig. 13 to form a Braille point.

Fig. 1 shows a plan view of a chip card ( 1 ) on which the word "phone card" is applied as a laser braille ( 2 ). In Fig. 2 the word "bank card" and in Fig. 3 the word "health insurance card" is applied.

In FIG. 4 a laser Braille shown (2) in height of the rear magnetic strip; is applied (3. 5 s Fig.). In addition, the standardized position areas for the chip module ( 4 ) and the embossed areas ( 5 ) which can be used as a printing block are shown in FIG. 4. The standardized height of embossments that can be used as a printing block is 0.46 mm.

In Fig. 6 is a schematic overview of the components of a laser marking machine which is suitable for generating the laser Braille (2) on a plastic card (1) is shown. Such a system is also described in DE 44 29 110 A1. A neodymium-YAG laser is preferably used for this. The actual laser-system (6) consists of a longitudinally between resonator mirrors (6 A) arranged Nd-YAG crystal (6 B), a high-power light source (6 C) for optically pumping the Nd-YAG crystal (6 B), a mode diaphragm ( 6 D), for the selection of a specific mode and a high-frequency electro-optical switch ( 6 E) for switching the coherent laser beam on and off, as a result of which pulse operation is achieved with a power which is sufficiently high for the generation of the laser Braille script ( 2 ) . The wavelength of the laser radiation in the Nd-YAG laser is 1.06 µm. The left resonator mirror ( 6 A) is partially transparent so that part of the laser radiation is coupled out of the resonator. This beam is now directed via a beam expansion optics ( 6 F) onto a two-coordinate beam deflection device ( 6 G) which is formed from two deflecting mirrors, each of which can be pivoted by a galvanometer motor. The beam diameter of the expanded beam is typically about 3 to 5 mm. The deflected, widened laser beam is then focused on the card ( 1 ) via a flat field lens ( 6 H) to form a laser writing spot ( 7 ).

FIG. 7 shows the local intensity profile of the laser writing spot ( 7 ) along the "spot diameter", which corresponds to a Gaussian distribution. The vast majority of the laser intensity (I) lies within a defined beam diameter (HWB), the so-called half-width. This is determined as the width of the intensity profile at half the maximum intensity (I _max. ). The half width is typically about 50 µm. Outside the beam diameter (HWB) defined by the half-width, the intensity decreases exponentially towards the outside.

With a typical duration for the charging phases of the pulsed Nd-YAG laser of 100 µsec, a pump power of 2 watts and a pulse length of 10 µsec, the power of the laser write pulse is 20 kWatt. In order to bring about visible and tangible changes in the plastic material, a threshold intensity in the writing spot ( 7 ) generated by the laser beam is necessary. This threshold intensity is sufficient only in the inner area of the writing spot, which is approximately determined by the half-value width (HWB); outside, the intensity is not sufficient to cause a change in the material structure.

To form a good tactile laser Braille point (20), it is advantageously provided that the chronologically successive laser writing spots (7) overlap on the card surface (1 A). The following laser writing spot ( 7 ) then hits plastic material in the overlap area, the structure of which has already been changed, which is accompanied by an increase in the absorption capacity of these areas. In this way, the structure-changing effect of the laser writing spot ( 7 ) in the overlap area is enhanced. For this reason, the distances between successive laser writing spots ( 7 ) should not be greater than the half-width (HWB) - cf. Fig. 9. For clarification, the intensity profiles of two laser writing spots ( 7 ) which only overlap in the edge areas are shown in Fig. 8; in this case there is neither a visible nor a palpable change in the overlap area.

Most cards (1) have z. B. to protect a on the card surface ( 1 A) print a transparent cover layer ( 1 C) in the form of a film or a varnish. This cover layer ( 1 C) is penetrated by the laser radiation during the generation of the laser braille ( 2 ). Due to the local temperature increase, the top layer ( 1 C) is softened, so that it yields to the bulging of the card surface ( 1 A) caused by the laser radiation and encloses the laser braille ( 20 ). It is also envisaged to use a cover layer ( 1 C) which has a certain absorption for the laser radiation, so that the cover layer ( 1 C) itself contributes to the formation of the Braille point ( 20 ).

In Fig. 10, a first advantageous embodiment is shown of a laser Braille point (20). In this case, the Braille dot emerges (20) as a semi-spherical elevation of the card surface (1 A). This contour corresponds to the Braille script as it is known on paper substrates.

In Fig. 11 a Braille point ( 20 ) is shown, which emerges as a truncated cone-shaped elevation from the map surface ( 1 A). In Fig. 12 Braille point occurs (20) as a cylinder-shaped elevation of the card surface (1 A).

It has been shown that laser braille dots ( 20 ) with a diameter parallel to the card surface of 0.8 to 1.4 mm and a height between 80 and 200 microns can be felt very well.

Different control methods for laser beam guidance are provided in order to form a laser braille writing ( 20 ) that is easy to feel. To form a Braille point (20) several hundred laser writing spots (7) must be created on the card surface (1 A). With the help of different laser beam guides (spatial arrangement of the successive laser writing spots), different profiles (hemispherical, truncated cone, cylindrical) can be realized for the Braille dots. Here, the areal distribution of the corresponding means of laser radiation in the card body (1 B) the applied energy dose with the profile of the laser Braille point (20).

In a variant it is provided that the chronologically successive laser writing spots ( 7 ) are guided on a spiral path around the center of the Braille writing point ( 20 ) to be formed. In Fig. 13 a labeling spiral is shown schematically; in reality, of course, the spiral turns are much closer together.

In another variant, the successive laser writing spots ( 7 ) are guided in concentric circles around the center of the Braille point ( 20 ) to be formed - cf. Fig. 14; in fact, the point density on the circular lines is much larger than shown.

In a further variant, the successive laser writing spots ( 7 ) are guided on a straight line running through the center of the Braille writing point ( 20 ) to be formed - cf. Fig. 15; For the sake of clarity, only a few of the star-shaped labeling lines are shown.

In addition, the laser braille dot ( 20 ) can be formed in two stages by writing two or more times with the laser radiation over the same locations.

The card body (1 A) itself may be formed of a laminate consisting of several layers or a single piece produced by injection molding map.

The orientation and arrangement of the laser Braille lettering (2) on the card surface (1 A) is selected in an advantageous manner so that a blind user includes unique information about the orientation in which the map is to be entered into a card reader. So z. B. Chip cards entered into terminals with a horizontally running card entry slot almost exclusively with the following orientation: Chip contact surfaces still on top and in front in the direction of insertion. This is indicated to a blind person by applying the laser braille on the right side and in the direction of insertion in the direction of insertion.

Claims (11)

1. A method for producing a plastic card in the form of an identification card, telephone card, credit card, health insurance card or the like, which has a tactile, alphanumeric information as Braille on the front and / or back, characterized in that the Braille document (2) forming the points (20) with the card surface (1 A) under the influence of laser radiation is formed sublime are formed by local charging of the plastic card (1) with laser radiation. 2. A method for producing a plastic card according to claim 1, characterized in that the relief structure designed as Braille ( 2 ) is generated by means of an Nd-YAG laser marking system in pulsed operation. 3. A method for producing a plastic card according to claim 2, characterized in that the areal distribution of the energy dose introduced by means of laser radiation within a Braille point ( 20 ) corresponds to the height profile of the laser Braille point. 4. A method for producing a plastic card according to claim 2 or 3, characterized in that the distance between the laser beam on the card surface ( 1 A) to form a Braille point ( 20 ), successive laser writing spots ( 7 ) is less than that Half-width (HWB) of the local intensity profile of the laser writing spot ( 7 ) on the card surface ( 1 A). 5. A method for producing a plastic card according to any one of claims 2 to 4, characterized in that the successive laser writing spots ( 7 ) generated by the pulsed laser beam on the card surface ( 1 A) each form a Braille dot ( 20 ) on one spiral path around the center of the Braille to be trained ( 20 ). 6. A method of manufacturing a plastic card as claimed in any of the preceding claims 2 to 4, characterized in that, generated by the pulsed laser beam on the card surface (1 A), chronologically successive laser writing pads (7) each for forming a Braille point (20) on concentric circles around the center of the Braille point to be trained. 7. A method of manufacturing a plastic card as claimed in any of the preceding claims 2 to 4, characterized in that the temporally successive laser writing spots produced by the pulsed laser beam on the card surface (1 A) (7) each for forming a Braille point (20) on be guided in a star shape through the center of the straight line to be formed Braille. 8. A method for producing a plastic card according to one of the preceding claims 2 to 7, characterized in that the laser inscription to form a Braille writing point ( 20 ) is carried out in at least two stages by the laser radiation at least twice over the same locations within the Braille to be formed Point is directed. 9. A method for producing a plastic card according to any one of the preceding claims, characterized in that a plastic card is used which has a cover layer ( 1 C) on the front and / or back which does not absorb the laser radiation, or absorbs it only very slightly, and the laser radiation through the cover layer ( 1 C) on the underlying card body layer ( 1 A) causes a change in material producing the Braille dots ( 20 ). 10. plastic card for use in the method of claim 9, characterized in that a plastic card consisting of a multi-layer laminate is used. 11. plastic card for use in the method according to claim 9, characterized in that an injection molding process manufactured plastic card is used.