GB2262910A - Mounting flexible printing plates on cylinders. - Google Patents

Abstract

A nylon printing plate 11 is removably attached to an associated cylindrical roller 12 by double-sided adhesive tape. The roller 12 is mounted on an alignment testing apparatus 20 having a scope 25 through which the printing plate 11, illuminated by a lamp 38, is viewed to check the printing plate 11 is correctly aligned on the roller 12 by matching register points X, Y on the printing plate 11 with crosshairs on the scope 25. The roller 12 is mounted in a printing machine to print labels on a backing sheet. The production of a reel of labels with coloured tabs indicating faults and subsequent spooling and packaging of the labels is described. <IMAGE>

Description

" method for manufacturina labels" This invention relates to a method for manufacturing labels.

According to the invention there is provided a method for manufacturing a roll of labels, comprising the steps; selecting an appropriate flexible printing plate and releasably mounting the printing plate on an associated roller, rotatably mounting the roller on a support, positioning a viewing scope having crosshairs alongside the roller and aligning the crosshairs with a first register point on the printing plate, rotating the roller to bring a second register point under the scope, checking for correct alignment of the second register point with the crosshairs and if incorrect, adjusting the printing plate on the roller and repeating the alignment checks on the first and second register points with the scope crosshairs until the printing plate is correctly positioned on the roller, mounting the roller on a printing machine, feeding into the printing machine a continuous backing sheet carrying a number of peel-off label blanks in series, printing a number of the label blanks with the printing plate, checking the quality of the printed labels and if within a preset desirable quality range, then running the printing machine to print a batch of labels, continuously monitoring the quality of the labels during printing and marking any portions of the backing sheet in which faults occur, reeling the backing sheet to form a reel of printed labels, mounting the reel of printed labels on a spooling machine in which the reel is unwound and fed onto preselected spools, each spool receiving a preset number of labels, correcting or removing any faults in the labels or backing sheet prior to winding the backing sheet with labels onto the spools, and packaging the spools.

In one embodiment of the invention, the printing plate carries a repeat design and the alignment of the printing plate is checked by aligning the crosshairs in turn with preselected corresponding points on a number of the designs.

In a further embodiment, faults in the backing sheet or printed labels are marked by attaching colour coded tabs to the backing sheet at the faults, the colour of the tabs indicating the type of fault.

Preferably the flexible printing plate is releasably mounted on the roller by sticking the printing plate on the roller with double-sided adhesive tape.

In some cases the process includes the step of varnishing the labels prior to reeling the backing sheet.

In another aspect the invention provides an apparatus for carrying out the method as described above, the apparatus including a printing plate alignment testing device having a frame, support means to rotatably support a roller on the frame, and a scope with crosshairs mounted on the frame for viewing rollers mounted on the support means.

Preferably the scope is movable on the frame for adjustment of the relative positions of the scope and a roller mounted on the frame.

In one embodiment the support means is a pair of spaced-apart V-shaped supports for reception of opposite ends of a roller.

In an alternative arrangement the support means is a pair of spaced-apart centres releasably engageable with centre holes at each end of a roller.

In a preferred embodiment a lamp is provided on the frame to illuminate a roller for viewing by the scope.

The invention will be more clearly understood by the following description of an embodiment thereof, given by way of example only, with reference to the accompanying drawings, in which; Fig. 1 is a flowchart illustrating a method according to the invention, Fig. 2 is a perspective view of an alignment testing device forming portion of apparatus for carrying out the method, Fig. 3 is a side elevational view of portion of the testing device, Fig. 4 is a plan view of the portion of the testing device shown in Fig. 3, Fig. 5 is a perspective view of portion of the testing device, Fig. 6 is an elevational view of a roller with a flexible printing plate mounted thereon as used in the method, and Fig. 7 is a perspective view of a reel of labels formed by the method.

Referring to the drawings, a method for manufacturing a roll of labels according to the invention will be described.

Firstly at a roller station 10 a nylon printing plate 11 is mounted on an associated cylindrical roller 12 (see Fig. 6).

The printing plate 11 carries a selected design for labels and is wrapped around an outer surface of the roller 12 and stuck to the roller 12 by double-sided adhesive tape. The roller 12 is then delivered to a testing station 15 having an alignment testing apparatus indicated generally by the reference numeral 20 and shown in Figs. 2 to 5.

The alignment testing device 20 has a frame 21. A number of associated pairs of spaced-apart V-shaped supports 22 for reception of ends 23 of the roller 12 are provided on the frame 21. A scope 25 having an eye piece 26 with crosshairs is mounted on the frame 21 adjacent the roller supports 22 on a mounting bracket 27. The mounting bracket 27 has a cross bar 28 which is parallel to the axis of a roller 12 mounted on the roller supports 22. The scope 25 is mounted on the cross bar 28 by a slide member 30 which is slidable along the cross bar 28. A locking screw 31 enables the slide member 30 to be secured at any position along the cross bar 28. A tubular lens housing 33 of the scope 25 is slidably mounted in a holder 34 on the slide member 30 and is secured in position by locking screws 35.The scope 25 can thus be moved towards or away from the roller 12 and secured in any desired position by the locking screws 35. A lamp 38 is secured on the mounting bracket 27 below the cross bar 28 for illumination of a roller 12 mounted on the roller supports 22. It will be seen from Fig. 2 that in this case the frame 21 carries a pair of scopes 25 and associated roller supports 22.

To test the alignment of the printing plate 11 on the roller 12, the scope 25 is adjusted on the frame 21 and the crosshairs of the eye piece 26 positioned at a first register point on the plate 11. For example, where the printing plate 11 carries a number of repeat designs 40 (as illustrated in Fig. 2) the crosshairs may be aligned with a point X on one design 40 and the roller 12 is then rotated on the supports 22 to bring a corresponding point Y on the next design 40 into register with the crosshairs of the scope 25. If the printing plate 11 is out of alignment then it can be quickly and easily adjusted and the testing repeated until the printing plate 11 is correctly aligned on the roller 12.

Then the roller 12 is mounted on an associated printing machine 50. A continuous backing sheet carrying a number of peel-off label blanks in series is fed into the printing machine 50 and a number of labels are printed as a test run 60. The labels are checked for quality and if they are within a preset desirable quality range then a print run 65 is carried out with the printing machine 50 to print a batch of labels which are reeled. If however there are any faults with the printing during the test run then these are corrected before carrying out the print run 65.

Fig. 7 shows a reel 52 of the printed labels 55 which are adhesively attached to a backing sheet 56. During printing the quality of the labels 55 is continuously monitored and if some problem occurs with for example, print quality the printing machine is immediately corrected and that portion of the wrapping sheet 56 carrying faulty labels is marked at a marking station 67 by tabs 57. If a first backing sheet 56 is used up and a second backing sheet 56 has to be used, then this is spliced to the first backing sheet 56 and the spliced join is also marked by a tab 57. Similarly if the backing sheet 56 breaks during a run when it is re-spliced it is marked by a tab 57. It will be noted that the tabs 57 are colour coded, the colour of the tabs reflecting the type of fault which occurs.

The reel 52 of printed labels is mounted on a spooling machine 69 (not shown) in which the reel 52 is unwound and fed onto preselected spools of any desired size for a particular application. A preset number of labels 55 are wound on each spool. Faulty labels marked by the tabs 57 are removed before spooling and any splices made during the printing are also either corrected or removed altogether depending on the quality required for the spooled labels. The spools of labels are then packaged and the packages sealed.

It will be appreciated that the alignment testing apparatus advantageously allows the alignment of the printing plate on the roller to be checked and corrected if necessary simply and quickly without having to mount the roller on the printing machine and carry out a test run to check the alignment.

The invention is not limited to the embodiment hereinbefore described which may be varied in both construction and detail.

Claims (13)

1. A method for manufacturing a roll of labels, comprising the steps; selecting an appropriate flexible printing plate and releasably mounting the printing plate on an associated roller, rotatably mounting the roller on a support, positioning a viewing scope having crosshairs alongside the roller and aligning the crosshairs with a first register point on the printing plate, rotating the roller to bring a second register point under the scope, checking for correct alignment of the second register point with the crosshairs and if incorrect adjusting the printing plate on the roller and repeating the alignment checks on the first and second register points with the scope crosshairs until the printing plate is correctly positioned on the roller, mounting the roller on a printing machine, feeding into the printing machine a continuous backing sheet carrying a number of peel-off label blanks in series, printing a number of the label blanks with the printing plate, checking the quality of the printed labels is within a preset quality range, then running the printing machine to print a batch of labels, continuously monitoring the quality of the labels during printing and marking any portions of the backing sheet in which faults occur, reeling the backing sheet to form a reel of printed labels, mounting the reel of printed labels on a spooling machine in which the reel is unwound and fed onto preselected spools, each spool receiving a preset number of labels, correcting or removing any faults in the labels or backing sheet prior to winding the labels onto the spools, and packaging the spools.

2. A method as claimed in claim 1 wherein the printing plate carries a repeat design and the alignment of the printing plate is checked by aligning the crosshairs in turn with preselected corresponding points on a number of the designs.

3. A method as claimed in claim 1 or claim 2 wherein faults in the backing sheet or printed labels are marked by attaching colour coded tabs to the backing sheet at the faults.

4. A method as claimed in any preceding claim wherein the printing plate is releasably mounted on the roller by sticking the printing plate to the roller with double sided adhesive tape.

5. A method as claimed in any preceding claim including the step of varnishing the labels prior to reeling.

6. A method substantially as hereinbefore described with reference to the accompanying drawings.

7. Labels whenever produced by the method as claimed in any preceding claim.

8. An apparatus for carrying out the method of any of claims 1 to 6, the apparatus including a printing plate alignment testing device having a frame, support means to rotatably support a roller on a frame, and a scope with crosshairs mounted on the frame for viewing rollers mounted on the support means.

9. An apparatus as claimed in claim 8 wherein the scope is movable on the frame for adjustment of the relative positions of the scope and a roller mounted on the frame.

10. An apparatus as claimed in claim 8 or claim 9 wherein the support means is a pair of spaced-apart V-shaped supports for reception of ends of a roller.

11. An apparatus as claimed in claim 8 or claim 9 wherein the support means is a pair of spaced-apart centres releasably engageable with centre holes at each end of a roller.

12. An apparatus as claimed in any of claims 8 to 11 wherein a lamp is provided on the frame to illuminate a roller for viewing the scope.

13. An apparatus substantially as hereinbefore described with reference to the accompanying drawings.