Abstract:
In a method for producing printed products of a similar kind in accordance with stored or input data, a machine-readable invisible or visible code for identification purposes is applied onto an outer side of the printed product. The visible code is removed during processing. The finished printed product is free of any visible code that could disrupt the appearance of the printed product.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The invention relates to a method for producing printed products of a similar kind in accordance with stored or input data, wherein the printed products are provided with a machine-readable code for their identification.  
           [0003]    2. Description of the Related Art  
           [0004]    The industrial manufacture of similar or identical printed products in printing and processing devices has been known for a long time. Such printed products are, in particular, catalogs or magazines which are produced in very large editions, as is well-known in the art, and then mailed. Such printing and processing devices comprise in their production line, in particular, a collecting device, an adhesive binding device or a stitcher, a trimmer, for example, a three-side cutter, as well as a stacking device.  
           [0005]    With such processing devices large editions of identical printed products can be produced which differ, for example, with regard to their labeling and/or their contents and/or their inserts or flyers. Such productions are also known by the term selective binding. The printed products which are collected and combined as desired are designed specifically for the recipient. Individual parts which are irrelevant to the recipient can be removed. For this purpose, a database is required which makes the data relevant for the recipient available in a processed form so that the product to be produced for the recipient is specifically defined.  
           [0006]    With a suitable selection of the manufacturing sequence it is even possible to produce the printed products in the sequence in which the mail delivery person places the products into the mailboxes on a clearly defined mail delivery route. Such as sequence is called mailing route-specific. With a corresponding preselection of the data sets and adherence to the sequence during the production, labor with respect to mail distribution is eliminated. These labor savings are made available to the manufacturer in the form of lower postage rates.  
           [0007]    Selective binding therefore has particularly the following advantages:  
           [0008]    for each recipient a precisely adjusted printed product can be produced;  
           [0009]    it is possible to provide inserts or flyers directed specifically to the needs of the recipient;  
           [0010]    personal remarks and messages can be printed during the production onto the printed products;  
           [0011]    irrelevant parts of the printed products can be eliminated for certain recipients and costs can be reduced in this way;  
           [0012]    postage can be saved.  
           [0013]    In order for selective binding to be possible, the control device of the processing device must know at any time which printed product is located where within the processing line. If this is not ensured, there is the risk that the printed products are structured wrongly and addressed with the wrong label so that, for example, the magazine for Mr. Miller has the name of Mr. Mayer printed on it. It is understood that such an error must not occur.  
           [0014]    Selective binding therefore requires a product sequence. In order to ensure this, it is known to correlate each printed product with a cell of the transport chain. The cells are guided past processing stations, wherein the device control must know the position of the cells and must assume that in each one of the cells the correlated printed product is located. Moreover, it is known to print onto the envelope of the printed products a barcode which identifies the printed product. However, there are many printed products for which a printed barcode is undesirable or disruptive.  
         SUMMARY OF THE INVENTION  
         [0015]    It is an object of the present invention to provide a method of the aforementioned kind which prevents the aforementioned disadvantages, is functionally reliable, and can be operated inexpensively.  
           [0016]    In accordance with the present invention, this is achieved in that the outer side of the printed product is provided with a machine-readable code which is invisible or in that a visible code is printed onto the printed product which is removed during processing. The finished printed product produced in this way thus contains an invisible code or no code at all and can be printed without any restriction on the front and back sides. The graphic design is thus not disrupted by a printed barcode as has been the case in the past.  
           [0017]    An especially suitable code according to a further embodiment of the invention is comprised of a plurality of dots which are so small that they are invisible to the eye. However, such dots are machine-readable. These dots can be, for example, in the form of a matrix, preferably a rectangular matrix.  
           [0018]    According to another embodiment of the invention, the code is printed by means of invisible ink.  
           [0019]    Preferably, such an ink is UV-reflective or IR-reflective. Such inks are not visible or only visible to a limited extent but machine-readable without problems.  
           [0020]    According to a further embodiment of the invention, the code is applied with a removable or erasable ink. Such inks are known. They can be removed by heat exposure or by means of a suitable radiation. Coding in this case is also not visible on the finished printed product.  
           [0021]    Moreover, the invention relates to a method for producing such printed products as well as to a device for performing such a method.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0022]    In the drawing:  
         [0023]    [0023]FIG. 1 shows schematically a printing and processing device according to the invention; and  
         [0024]    [0024]FIG. 2 is a printed product which is produced according to the method of the present invention.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0025]    The printing and processing device  1  schematically illustrated in FIG. 1 has a collecting device  3  comprising a collecting channel  4  and several sheet feeders  5  ( 5   a / 5   b ). The sheet feeders  5 , known in the art, are arranged along a collecting channel  4 . Each one of the sheet feeders  5  is manually or automatically supplied according to the specific needs with the printed sheets. The task of the sheet feeders  5  is to individualize the printed sheets and to feed them in a synchronized fashion onto the chain  2  of the collecting channel  4  comprised of identical sections. For each machine cycle, the collecting chain  2  travels an exact distance along the conveying path. In this way, it is possible that each chain section receives one printed sheet from each sheet feeder  5 . By means of a control device  26  controlling operation of the printing and processing device  1 , the sheet feeders  5  are activated or deactivated so that at the end  4   a  of the collecting channel  4  a printed product  7  comprised of the correct number and type of printed sheets has been compiled. Each feeder  5   b  is preferably provided with an integrated printer  6  that makes it possible to print onto the printed sheet a text which is correlated directly with the corresponding printed product. The printed products can be printed with different texts which are, for example, correlated with the person (recipient) and/or the subject matter. Such a text can be different, for example, for the recipient residing in city A different from that for the recipient residing in city B. The printed pre-product  7  at the end  4   a  of the collecting chain  4  is, for example, a book block that is not yet bound.  
         [0026]    The printed pre-products  7  collected in the collecting device  3  are then transferred in the direction of arrow  8  in synchronized cycled fashion to the adhesive binding device  9 . In this adhesive binding device  9  the folds at the back of the printed pre-products  7  are removed by cutting or milling. Subsequently, the spine is prepared by roughing, notching and brushing for the application of the adhesive. After the adhesive has been applied, an envelope  29  (FIG. 2) is pressed by means of an envelope feeder  11  against the spine of the book block or the printed pre-product  7 . If it is desired to be able to select during the production process from a selection of different envelopes  29 , the use of an envelope feeder  11  with several stations is required. The selection of the matching envelope  29  is realized again by means of the control device  26 . At the end of the adhesive binding device  9 , a discharge chute can be provided for eliminating faulty products. Up to the end of the binding device  9 , the printed pre-products  7  and the printed products  13  provided with an envelope  29  are always correlated with a certain machine cycle and can be identified at any time by the device control  26 . In front of the end of the binding device  9  a printer  12  is arranged with which a code  30  can be printed onto the outer side of the envelope  29 . According to FIG. 2, the code  30  is comprised of a plurality of dots  31 . This code  30  is machine-readable and identifies the printed product  13 . In addition, by means of the same printer  12 , it is also possible to print text, for example, an address onto the product. The printer  12  is controlled via a control line  27  by the control device  26  which comprises a database for the product-specific data or is connected to such a database. This database contains the product-specific data in processed form. The data are preferably processed according to a manufacturing sequence so that the printed products  13  can be produced in the sequence in which the mailman has to place the products into the mailboxes in accordance with his clearly defined mail delivery route.  
         [0027]    The code  30  according to FIG. 2 forms a rectangular dot matrix. The dots  31  are so small that they are not visible or hardly visible by the naked eye. Moreover, the spacings D between neighboring dots  31  of a matrix  32  are several times greater, for example, at least five times greater, than the diameter of the dots  31 . In the printed product  13  according to FIG. 2, the dots  31  are printed onto the front side  29   a  of the envelope  29 . The area of the code  30  can be a partial area of the front side  29   a  or can be the entire area. The code  30  could also be applied onto the spine  29   b  or onto a cut side  13   a.  Finally, the code  30  can be printed onto the backside of the envelope  29 , not illustrated in FIG. 2. The dots  31  are so small that they cannot be recognized as such as a part of a graphic illustration, for example, a photographic illustration, and therefore do not disrupt this illustration visually. The presence or absence of a dot  31  at an interception of the matrix however can be easily determined by machine reading. Suitable optical readers are known to a person skilled in the art. As an alternative, coding could also be provided by means of ink which intensively reflects particularly UV light or IR light. Such an ink is invisible to the eye but can be machine-read in suitable light. The code  30  could also be printed with an ink which is erasable. Such inks are known. Erasing is realized, for example, by heat exposure. In this case, the code  30  is also invisible on the finished printed product. Finally, the code  30  can also be applied to a foil, not illustrated, such that the code  30  can be removed from the envelope  29 .  
         [0028]    The printed products  13  provided with the envelope  29  and the code  30  and still warm are transferred to a cooling stretch  14 . This cooling stretch  14  is comprised for reasons of simplification and cost reduction preferably of several transport belts, not illustrated. Moreover, the cooling stretch  14  can be comprised over portions thereof of parallel sections  14   a,    14   b  which at the beginning and the end are provided with switches  15  and  16 . The purpose of such a two-track partial stretch is that during a disruption-free production all products can be transported via the section  14   a  while the second section  14   b  is not used (empty). When in the area downstream of the switch  16  a disruption occurs which causes the transport belts to stop, the sections  14   a  and the collector  3  are stopped and all printed products  13  which still arrive in front of the switch  15  are then guided onto the still empty stretch  14   b.  The receiving capacity of the section  14   b  must be at least so large that the entire contents of the adhesive binding device  9  can be received therein. In this way, it can be prevented that the binding device  9  filled with pre-products  7  must be stopped.  
         [0029]    It is important that the printed products  13  in the area of the cooling stretch  14  are provided with the above-mentioned code  30 . Even in the case of disruptions or other irregularities in the area of the cooling stretch  14 , each printed product  13  can be identified by means of the code  30 . It is not possible for the control device  26  to control the printed products  13  in the area of the cooling stretch  14 . It is also impossible to recognize whether a printed product  13  in the area of the cooling stretch  14  has been removed and is thus missing. Also, the device control  26  is not capable of detecting switching of two printed products  13 .  
         [0030]    Downstream of the cooling stretch  14  the printed products  13  are then trimmed in a trimmer  17 . This trimming device  17  is particularly embodied as a three-side cutter which cuts the printed products  13  on three open sides. The actual finishing process is thus complete.  
         [0031]    Downstream of the cutting device  17  the printed products  13  are supplied on a transport belt  18  to a stacking device  19  in which the printed products  13  are stacked and turned by 90 degrees. In a removing device  20  the printed products  13  are subsequently removed from the stack and then supplied to an insertion device  21 . At the same time, the codes  30  of the printed products  13  are read by a reading device which is connected by a control line  27  to the control device  26 . The insertion machine  21  now adds to the printed products  13 , based on the address of the recipient, an insert or flyer, not illustrated. Since the printed products  13  can be identified by means of the code  30  via the control device  26  and the reading device  22 , different inserts, or no inserts at all, can be added in accordance with the data of the recipient. The printed product  13  for Mr. Miller, for example, can receive the insert A and the printed product  13  for Mr. Mayer can receive the insert B. Subsequently, the printed products  13  are then printed by means of a printer  25 , also controlled via the control line  27  connected to the control device  26 , with the correct address.  
         [0032]    Subsequently, the printed products  13  can be wrapped in foil by a wrapping machine  23  and then transferred to a stacker  24 . By means of a belt  28 , the mailing-ready stacked products  13  are discharged. These stacks of the printed products  13  are preferably arranged in the order of the mail delivery route. Such a stack contains, for example, all printed products  13  which are to be placed into the mailboxes by the mailman on his clearly defined route.  
         [0033]    While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.