Abstract:
A composite tape supply for use in a tape printer comprising an image receiving layer; a backing layer; and a liner layer.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a tape printing apparatus, a composite tape supply and to a method of printing on a composite tape to form a label. In particular, the present invention relates to a tape printing apparatus for printing an image, such as a background image, so that the image is printed across the length of the entire label. 
       BACKGROUND OF THE INVENTION 
       [0002]    Printers capable of printing background images include direct thermal printers. 
         [0003]    For example, EP 1638780 describes a method of printing a label in which a multicoloured image is produced on the tape by direct thermal transfer in a single pass of the tape past the print head, resulting in a high quality colour image. 
         [0004]    When printing a colour background such as a single block colour, it is possible to print a background which covers the entire width of the label since the width of the print head exceeds the width of the tape. However, printing across the entire length of the label in a single pass is not currently possible due to the location of the cutter in relation to the location of the print head.  FIG. 1  ( a ) shows the relative positions of the print head ( 60 ), the platen ( 80 ), the cutter ( 20 ) and the image receiving tape ( 44 ) in a tape printing apparatus during printing.  FIG. 1  ( b ) shows the position of the tape ( 40 ) at various stages of printing. As shown in  FIGS. 1  ( a ) and ( b ) the print line ( 90 ) is at a distance x from the cutting line ( 100 ). Consequently, after a first label is cut from the tape, a distance x exists between the end of the tape and the printing location. Accordingly the label is printed with a blank leader of length x. Examples of labels printed in this manner are shown in  FIG. 2 . 
         [0005]    Often a blank trailer of the same length is added to the label to give the label a symmetrical appearance. However a blank leader and trailer are usually not desirable, especially when labels are printed with a background therefore making the blank regions noticeable. 
         [0006]    The inventors of the present invention have also identified that the image receiving tape may be reversed such that the end of the tape is closer to the print line, therefore decreasing the length of the blank leader. However it is necessary for a portion of tape to be downstream of the print line so that the platen maintains sufficient contact with the tape in order to advance the tape. If there is not a sufficient amount of tape downstream of the print line it is necessary to drive the tape using rollers positioned upstream of the platen. 
         [0007]    The inclusion of rollers increases the size of the printer and the complexity of the driving mechanism. Providing drive rollers upstream of the print head can obscure the print station and prevent the tape from entering between the print head and the platen. 
         [0008]    Using rollers upstream of the print head to feed the tape between the print head and the platen can cause the tape to distort. This is caused by the force required to feed the tape between the print head and the platen. This force can result in a curl in the tape which makes it difficult to know exactly when the tape has been fed between print head and platen and therefore where the print start position is. 
         [0009]    Another disadvantage caused by feeding the tape between the platen and the print head using rollers is that it is difficult to correctly align the tape beneath the print head. when you have a small tape which is moved between a print head and platen. This causes the printed image to be incorrectly positioned on the tape. 
         [0010]    A similar problem is evident in printers such as ink jet printers having drive rollers arranged downstream of the print head. When the tape is fed between the drive rollers that are down stream of the print head the tape is likely to distort and to be misaligned. 
         [0011]    Embodiments of the present invention aim to address the above-mentioned problems. 
       SUMMARY OF THE INVENTION 
       [0012]    According to a first aspect of the present invention, there is provided a composite tape supply for use in a tape printer comprising an image receiving layer, a backing layer and a liner layer. The backing layer may be adhered to the image receiving layer. The liner layer may be adhered to the backing layer. The liner layer may be removable from the backing layer to provide a label comprising the image receiving layer and the backing layer. Removal of the backing layer may permit the image receiving layer to be stuck to a surface. 
         [0013]    According to a second aspect of the present invention there is provided a cassette for use in a tape printer comprising a body housing a supply of composite tape having a image receiving layer and a liner layer, a supply spool for supplying the composite tape and a take up spool for receiving said liner layer. 
         [0014]    According to a third aspect of the present invention there is provided a tape printer comprising a cassette receiving portion for receiving a cassette containing image receiving tape, a print head for printing an image on a tape, a first support for supporting a take up spool in the cassette, a drive means for driving a tape passed the print head in a first direction and a second direction and a control means for controlling the drive means in order to position the tape relative to the print head. 
         [0015]    According to a fourth aspect of the present invention there is provided a method of printing on a composite tape supply comprising the steps of printing on an image receiving layer of the tape supply, separating the image receiving layer from a liner layer of the composite tape supply, cutting the printed image receiving layer to form a label and retaining the liner layer in the housing of the printer. 
         [0016]    According to a fifth aspect of the present invention there is provided a method of printing an image on an image receiving tape comprising advancing the tape in a first direction such that the end of the image receiving tape is a predetermined distance upstream of the printing location, printing on the tape while advancing the tape in a second direction by means of advancing a liner attached to the image receiving tape and cutting the image receiving tape at a cutting location to form a label. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0017]    For a better understanding of the present invention and as to how the same may be carried into effect, embodiments of the present invention will now be described with reference to the following drawings: 
           [0018]      FIG. 1(   a ) shows the relative positions of the print head, cutter and image receiving tape during printing according to the prior art; 
           [0019]      FIG. 1(   b ) shows the image receiving tape at various stages of printing, according to the prior art; 
           [0020]      FIG. 2  shows examples of labels produced with blank leaders according to the prior art; 
           [0021]      FIG. 3  shows a schematic diagram of a tape printing apparatus according to an embodiment of the present invention; 
           [0022]      FIG. 4  shows schematically control circuitry for controlling a tape printing device embodying the present invention; 
           [0023]      FIG. 5  shows a schematic cross sectional view of a tape printer according to an embodiment of the present invention; 
           [0024]      FIG. 6  shows a schematic cross sectional view of a composite tape according to an embodiment of the present invention; 
           [0025]      FIG. 7  shows a schematic cross sectional view of a tape printer according to a further embodiment of the present invention; 
           [0026]      FIG. 8  shows a schematic cross sectional view of a tape printer according to a further embodiment of the present invention; 
           [0027]      FIG. 9  shows the image receiving tape at various stages of printing, according to a further embodiment of the present invention; 
           [0028]      FIG. 10  shows the image receiving tape at various stages of printing, according to a further embodiment of the present invention; 
           [0029]      FIG. 11  shows a cross sectional view of a cassette according to the present invention; 
           [0030]      FIG. 12  shows a schematic cross sectional view of a tape printer according to a further embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0031]      FIGS. 1 and 2  indicate prior art and have already been discussed in the preamble of this specification. 
         [0032]      FIG. 3  shows a schematic diagram of a tape printing apparatus  28  according to an embodiment of the present invention. The tape printing apparatus comprises a keyboard  30  and a cassette receiving bay  32 . The keyboard has a plurality of data entry keys  34  such as numbered, lettered and punctuation keys for inputting data to be printed as a label and function keys for editing the input data. The keyboard may also have a print key  36  which is operated when it is desired that a label be printed. Additionally an on/off key  38  is also provided for switching the tape printing apparatus on and off. 
         [0033]    The tape printing apparatus has a liquid crystal display (LCD)  10  which displays the data as it is entered. The display allows the user to view all or part of the label to be printed which facilitates the editing of the label prior to its printing. Additionally, the display is driven by a display driver (not shown). 
         [0034]    Basic circuitry for controlling the tape printing device  28  is shown in  FIG. 4 . There is a microprocessor chip  200  having a read only memory (ROM)  202 , a microprocessor  201  and random access memory capacity indicated diagrammatically by RAM  204 . The microprocessor chip  200  is connected to receive label data input to it from a data input device such as a keyboard  30 . The microprocessor chip  200  outputs data to drive a display  10  via a display driver chip  209  to display a label to be printed (or a part thereof) and/or a message for the user. The display driver alternatively may form part of the microprocessor chip. Additionally, the microprocessor chip  200  also outputs data to drive the print head  60  so that the label data is printed onto the image receiving tape to form a label. The microprocessor chip  200  also controls a motor  207  for driving the tape. The manner in which the tape may be driven will be discussed hereinafter. Finally the microprocessor chip  100  also controls the cutting mechanism  58  to allow a length of tape to be cut off. 
         [0035]    Reference is made to  FIG. 5  which shows in plan view a tape printing device  28  according to an embodiment of the present invention which has a cassette  50  arranged therein. This cassette contains a supply of direct thermal material liner tape  40  (described hereinafter) provided on a supply spool  88 . The cassette also contains a liner take up spool  89  and spindle  87 . The cassette  50  is located in a cassette bay  32 . The cassette bay  32  also accommodates at least one thermal print head  60  and a platen  80  which cooperate to define a print zone  51 . Other arrangements for the printing are described in more detail hereinafter. The print head  60  is able to pivot about a pivot point  54  so that it can be brought into contact with the platen  80  for printing and moved away from the platen  80  to enable the cassette  50  to be removed and replaced. In the operative position, in one embodiment of the invention the platen  80  is rotated to cause the tape  40  to be driven past the print head  60 . 
         [0036]    Reference is now made to  FIG. 6  which shows a schematic diagram of a liner tape  40  according to an embodiment of the invention. The liner tape comprises an image receiving layer  162  on which an image is printed, an adhesive layer  168  which attaches a releasable backing layer  164 , and an adhesive layer  169  which attaches the backing layer to a liner layer  166 . According to an embodiment of the invention the material forming the liner layer  166  may be polyethylene or polyester. According to an alternative embodiment of the invention the material forming the liner layer  166  may be paper. The material that may be used for the liner layer is not limited to these examples. 
         [0037]    In a preferred embodiment of the invention the backing layer  164  is paper and the liner layer  166  is polyethylene. Since the liner layer is provided on the opposite side of the tape to the image receiving layer  162 , the liner layer  166  is the inner layer of the liner tape  40  when the liner tape  40  is wound on the supply spool. Therefore when the liner tape is on the supply spool the liner layer follows a slightly shorter radius than the image receiving layer. It is therefore advantageous for the liner layer to be formed from a material, such as polyethylene, which is flexible to avoid the liner layer from becoming separated from the layers of the tape when the tape is wound on the supply spool. 
         [0038]    In a preferred embodiment of the invention the image receiving layer is a direct thermal image receiving layer. 
         [0039]    The releasable backing layer is provided in order to cover the adhesive layer  168  of a label which is formed when the tape  40  is cut and ejected from the printer. The user may then peel off the backing layer  164  from the label in order to adhere the label to a surface. 
         [0040]    According to one embodiment of the invention the lower surface of the releasable backing layer  164  that contacts the adhesive layer  169  has a lower release value than the upper surface that contacts the adhesive layer  168 . This allows the liner layer to be peeled away more easily from the backing layer than the backing layer can be peeled away from the image receiving layer. This may be achieved by providing a different coating on the upper surface and the lower surface of the backing layer  164 . 
         [0041]    An example showing typical release values on the upper and lower surfaces of the backing layer are given in Table 1. Table 1 shows the test results for a paper backing layer of 63 gsm. The paper has a thickness of 60 μm and is silicone coated on 2 sides with differential release. The test results are provided for two types of adhesive. The test is executed with a 25 mm width tape which is peeled under an angle of 180°. 
         [0000]    
       
         
               
             
               
               
             
               
               
               
             
               
               
             
               
               
               
             
               
               
             
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 TYPICAL RELEASE VALUES (TEST CONDITIONS              20187:          ) 
               
             
          
           
               
                   
                 ADHESIVE 
               
             
          
           
               
                   
                 ITAC A7055 
                 Tesa Tape 7475 
               
               
                   
                 Rubber based adhesive 
                 Acrylic adhesive tape 
               
             
          
           
               
                   
                 TEST METHOD 
               
             
          
           
               
                   
                 (STM 1 &amp; 157) 
                 (STM 152 &amp; 157) 
               
             
          
           
               
                   
                 RELEASE SPEED 
               
               
                   
                 (g/25 mm) 180° peel at 300 mm/min (low speed) 
               
               
                   
                   
               
             
          
           
               
                 Side 1 (A12 Release) 
                 40 
                 25 
               
               
                 Side 2 (A00 Release) 
                 10 
                 7 
               
               
                   
               
               
                             indicates data missing or illegible when filed 
               
             
          
         
       
     
         [0042]    In an alternative embodiment of the invention the tape only includes image receiving layer  162 , adhesive layer  168 , and liner layer  166 . If the adhesive is arranged to remain on the image receiving layer when the image receiving layer and the liner layer have been separated the tape printer will output linerless adhesive labels. If however the adhesive is arranged to remain on the liner when the image receiving layer and the liner layer have been separated the tape printer will output non-adhesive labels. 
         [0043]    In a further alternative embodiment of the present invention, the image receiving layer is a thermal transfer tape. This embodiment will be discussed further in relation to  FIG. 7  discussed hereinafter. 
         [0044]    In a further alternative embodiment of the present invention the image receiving layer may comprise die cut labels arranged on the releasable backing layer  164 . According to this embodiment the adhesive layer  168  is only provided in the areas between the die cut labels and the sheets. The die cut labels may be available in different sizes. For example different label sizes may be suited to different applications such as address labels and CD labels. 
         [0045]    In operation, the platen  80  is driven by a DC motor (see  FIG. 4 ) so that it rotates to drive the direct thermal material liner tape  40  through the print zone  51  of the tape printing device  28  during printing. In this way, an image is printed on the tape and fed out from the print zone  51 . In an alternative embodiment of the invention the motor may be a stepper motor. 
         [0046]    According to an embodiment of the invention the liner layer  166  is driven in order to transport the image receiving layer through the printer. In a preferred embodiment of the invention the liner layer is separated from the image receiving layer  162  before the image receiving layer exits the printer and is cut to form a label. The liner layer that has separated from the image receiving layer is stored within the printer so that if the tape is reversed such that the image receiving layer is upstream of the print head there is a portion of the liner tape that remains downstream of the print head in order to transport the image receiving layer past the print head. 
         [0047]    The tape may be driven in the forward direction under the rotation of the platen or the take up spool. When driving the tape forward it is necessary to drive the take up spool in order for the liner to be wound onto the take up spool. The take up spool may be driven independently of the platen or driven under the rotation of the platen which may be driven by the motor. In one embodiment of the invention the supply spool may also be rotated in the forward direction to prevent tension in the tape. 
         [0048]    The tape may be driven in the reverse direction by rotating the platen in the reverse direction. In one embodiment of the invention the supply spool may be driven in the reverse direction to rewind the tape. In one embodiment of the invention the supply spool is only driven in the reverse direction if tape is to be rewound a large amount compared to the distance between the supply spool and the print head, for example more than 2 cm. 
         [0049]    In the preferred implementation, the platen will be driven during reverse feeding and forward feeding. 
         [0050]    In an alternative embodiment of the present invention a needled roller assembly may be used to drive the tape in a forward and reverse direction. In this embodiment it is not necessary to drive the platen. The needled roller assembly may be provided outside the cassette. 
         [0051]    According to an embodiment of the invention, after the liner tape passes through the print zone the liner layer is drawn back into the cassette onto the liner take up spool  89 . The liner layer is drawn over spindle  87  and is advanced in a direction which is at an angle in excess of 90 degrees to the direction of the tape through the print zone as shown in  FIG. 5 . The angle of 90 degrees is only given as an example. In alternative embodiments of the present invention the angle may be more than or less than 90 degrees, provided that the change in direction of the liner tape is sufficient to separate the liner layer from the rest of the tape. The rigidity of the tape layers cause the backing layer  164  to separate from the liner layer  166  and for the image receiving layer and the backing layer to advance towards the cutter  20  and out of the tape printer at exit  280 . Therefore when the tape  40  passes through the cutting location the tape only comprises the image receiving layer  162  and the backing layer  168  attached by adhesive layer  164 . 
         [0052]    In an alternative embodiment of the invention the spindle  87  may be replaced by a thread extending across the width of the liner layer, a blade like projection or two small pins arranged opposite each other at opposite edges of the liner layer. 
         [0053]    In an alternative embodiment of the invention the liner layer may be separated from the rest of the tape by feeding the tape against a member, such as a blade or a thread, such that the rest of the tape is lifted away from the liner layer. According to this embodiment it is not necessary to change the direction of the liner layer in order to separate the liner layer from the rest of the tape. After the liner layer has been separated from the rest of the tape it may be guided towards the take up spool. 
         [0054]    In an alternative embodiment of the present invention the tape may be cut before the liner layer is separated from the rest of the tape. In this embodiment the cutter  20  would form a partial, or ‘tab’ cut that extends through the image receiving layer and the backing layer but not the liner layer. 
         [0055]    The image is printed by the print head  60  on the tape  40  on a column by column basis with the columns being adjacent one another in the direction of movement of the tape  40 . Pixels are selectively activated in each column to construct an image in a manner well known in the art. The DC motor is provided with a shaft encoder for monitoring the speed of rotation of the motor. The control of the speed of the motor is achieved by the microprocessor chip  200  (see  FIG. 4 ) to generate data strobe signals each of which causes a column of pixel data to be printed by the print head  60 . The shaft encoder may alternatively be located on the platen, or any other component whose rotation correlates with the position of the tape. 
         [0056]    In an alternative embodiment the position of the tape may be detected using a detector that detects markings on the tape. The markings may be provided on the liner layer. 
         [0057]    The tape printing device includes at cutting location  53  a cutting mechanism  58  which carries a blade  20 . The blade  20  cuts the image receiving tape  40  then enters a slot  55  located in the cassette  50 . Alternatively the cutting mechanism may be arranged above a slot provided in the wall of the printer. 
         [0058]    It is understood that other embodiments of the tape printer may be envisaged. For example, the tape printer of the present invention may be a PC printer rather than a stand-alone printer. In such a printer, a keyboard and display means are not essential as the data may be input and displayed on the PC. The PC then acts as an input device for the printer. Alternatively, other apparatus may be used to input data to the printer for printing. For example, in an embodiment of the invention a digital camera may be used to input data to the tape printing device for printing. Images may alternatively be input using a smart card, chip card, memory card or the like. 
         [0059]    Tape printers embodying the present invention can also be arranged to do thermal transfer printing, that is using an ink ribbon.  FIG. 7  shows a schematic diagram of a cassette receiving bay  32  in the tape printing apparatus when arranged to do thermal transfer printing. In this embodiment an ink ribbon cassette  24  is installed together with the image receiving tape cassette  50 . The ink ribbon  45  passes through the print zone together with the image receiving tape. According to this embodiment of the invention the image receiving layer  162  is an ink receiving thermal transfer layer. 
         [0060]    In one modification the ink ribbon is included in the same cassette as the image receiving tape.  FIG. 11  shows a diagram of a cassette  203  that includes both the liner tape and an ink ribbon. The ink ribbon  45  is provided on an ink ribbon supply spool  201  and ink ribbon take up spool  202 . The cassette  203  also includes liner tape  40  that is provided on a supply spool  88 ′ and liner layer take up spool  89 ′. 
         [0061]    It should be emphasised that embodiments of the invention are not limited to the examples of the tape materials given in this application. Embodiments of the present invention can be used with full colour direct thermal materials, with direct thermal materials which give a selection of two or more possible colours or materials which may be printed on transferring ink from an ink ribbon. 
         [0062]    It should further be emphasised that embodiments of the invention are not limited to the thermal printing technology. Embodiments of the present invention can use inkjet print technology, laser print technology or any other technology to produce an image on an image receiving layer. In one of the embodiments of the present invention the printhead may be an inkjet line print head which prints over the entire width of the tape without a translation movement in the direction perpendicular to the printing direction.  FIG. 12  shows an example of an ink jet printer. An ink jet line print head  204  is arranged between a needle roller assembly  206 . The needle roller assembly transports the tape  40  beneath the print head in a printing direction A. The liner tape is supplied on supply spool  88 ″. The liner layer take up spool  89 ″ takes up the liner layer  166  before the image receiving layer  162 , and backing layer if present, exit the printer. 
         [0063]    Preferred embodiments of the present invention are arranged so that information is automatically provided to or detected by the tape printer about the capabilities of the material. In other words whether the material is full colour, a thermal transfer material, a direct thermal material only providing one colour or a colour direct thermal material providing two or more colour options and if so what those colour options are. This information can be provided in a number of different ways. For example, the tape supply and/or cassette may have an element which provides the necessary information. In alternative embodiments of the present invention, the user may be able to set this from the keyboard. In other words, the user will provide the tape printer with information as to the type of tape material so that the tape printer can be controlled accordingly. 
         [0064]    Reference is now made to  FIG. 8  which shows a tape printer  28 ′ and cassette  50 ′ according to another embodiment of the present invention. In this embodiment, cassette  50 ′ includes a roller  91  positioned near the opening of the cassette, against the tape  40 . The print head  60  in the printer  28 ′ is arranged such that the roller  91  and the print head correspond to form a print zone  51 .′ 
         [0065]    The inclusion of a roller in the cassette replaces the requirement for a platen in the cassette receiving bay of the printer. This allows the cassette to be loaded in the printer more easily. Cassette  50 ′ may be side loaded or top loaded into the printer. 
         [0066]    Reference is now made to  FIG. 9  which shows the relative positions of the print head  60 , the platen  80  and the cutter  20  of a tape printer  28 , together with the corresponding positions of the image receiving layer of tape  40  at various steps of printing, according to an embodiment of the present invention. The print line  90  indicates the position where printing occurs. Cutting line  100  indicates the position where a full cut is made. 
         [0067]    At step S 1  the first label is separated from the remaining tape supply  40  by the cutter  20  performing a full cut at cutting line  100 . As shown, the full cut is made at a short distance downstream of the last printed line. Since it is difficult to cut precisely at the last printed line, this ensures that the image on the label extends up to the trailing edge of the label. 
         [0068]    At step S 2 , the tape supply  40  is advanced a small predetermined distance and another full cut is made. This ensures that any printed image remaining from the previous label is removed. Since the section of tape which is cut off is small, it will not reach the tape exit  280  of the tape printer  28 . Instead, the section of tape which is cut off is allowed to fall into a waste box (not shown) which is located below the cutting location. 
         [0069]    At step S 3 , the tape is reversed such that the leading edge of the cut image receiving layer  162  is upstream of the print line  90 . 
         [0070]    At step S 4 , the tape is advanced towards the print line by driving the liner  166  forward. This may be achieved by driving either the platen  80  or the liner take up spool  154 . When the leading edge of the image receiving layer  162  reaches the print line  90 , printing is commenced. In another embodiment of the invention printing commences shortly before the image receiving layer reaches the print line in order to ensure that the image is printed at the edge of the tape. 
         [0071]    At step S 5 , when printing is completed the tape is forwarded so that the cutting line  100  is downstream of at least the last printed line. A full cut is then made, separating the label from the tape supply  159 . 
         [0072]    According to the above embodiment of the present invention, it is possible to produce labels that do not have blank leaders or trailers without the need for separate means for driving the tape when the image receiving tape is upstream of the print head. 
         [0073]    In an alternative embodiment of the invention the cutter  20  may be arranged to perform a tab cut at step S 2  which cuts through the image receiving layer only. When the liner is drawn over spindle  87 , the liner  166  and adhesive  169  are separated from the image receiving layer  162 , adhesive  168  and backing layer  166 . The portion of the tape between the two tab cuts can for example be used as a transition zone between two entire printed labels. By performing a tab cut at step S 2  rather than a full cut the waste portion of the tape is output together with the label. The label can be peeled from the backing layer while the waste portion stays on the backing layer. 
         [0074]    In a further alternative embodiment the full cut and the tab cut may be made by two separate blades wherein the blade performing the tab cut is performed upstream of the blade performing the full cut. According to this embodiment it is not necessary to advance the tape at step S 2  since the full cut and tab cut can be made simultaneously at step S 1 . 
         [0075]    In a further alternative embodiment of the present invention, labels may be printed that do not have a printed background. According to this embodiment it is not necessary to perform two cuts to remove a portion of tape between two consecutive labels. This embodiment is described in relation to  FIG. 10 . 
         [0076]    At step S 11  the first label is separated from the remaining tape supply  40  by the cutter  20  performing a full cut at cutting line  100 . The full cut is made at distance A upstream of the last printed line. The distance A can be any value starting from zero. 
         [0077]    At step S 12  the tape is reversed such that the leading edge of the cut image receiving liner tape is upstream of the print line  90 . 
         [0078]    At step S 13  the tape is advanced towards the print line. This may be achieved by driving the platen or the liner take up spool, or both. When the leading edge of the image receiving layer  162  reaches the print line  90 , printing can start if required. The printer starts printing when the leading edge is a distance B downstream of the print line. The distance B can be any value starting from zero. 
         [0079]    At step S 14 , when printing is completed the tape is advanced and the label is cut by a full cut at a distance A′ upstream of the last printed line. The distance A′ can be any value starting from zero. 
         [0080]    According to the above embodiment of the present invention, it is possible to produce labels that have leaders or trailers starting from zero without the need for separate means for driving the tape when the image receiving tape is upstream of the print head. 
         [0081]    In an alternative embodiment, the tape is reversed at step S 12  to the position calculated by the controller as the starting position for printing. 
         [0082]    It should be appreciated that embodiments of the invention are applicable to continuous tape and also, where appropriate die cut labels arranged on a continuous backing layer.