JPH05278207A - Registering method and apparatus in printing - Google Patents

Abstract

PURPOSE:To perform the registering of printing by detecting even the register marks printed on any web by any ink and controlling the interval between the register marks. CONSTITUTION:Two register marks 16, 16' printed on a web 15 are irradiated with ultraviolet rays or visible light from a detection head 12 having an optical means built therein and the reflected light or emitted light thereof is again received by the light detection part of the detection head 12. The obtained optical data is sent to a control part having a photoelectric conversion part, a power supply and a light source through a fiber unit 6 and converted to an electric signal to be sent to a control part 23 by a shield wire 24. The control part 23 controls the compensator roller of a printing press on the basis of the inputted electric signal to perform the registering of printing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a registration method and apparatus for printing in which a plurality of registration marks printed on a web are detected and the positional relationship between them is controlled to adjust the registration of printing. Is.

[0002]

2. Description of the Related Art As a registration method in printing,
A method of printing a register mark for each plate and controlling the positional relationship of these register marks is widely used. Therefore, conventionally, a method of visually identifying and controlling the mutual positional relationship of the register marks was initially adopted. Here, the registration mark is printed with visible ink (visible registration mark).
There are some that are printed with transparent ink (transparent printer marks).
In particular, when visually detecting a transparent register mark, an ultraviolet lamp was used to perform the operation at a low speed.

In recent years, a method of compensating for print misalignment by detecting register marks by an optical sensor and comparing their positions with each other has become widespread. Here, in the case of a visible register mark, the visible light source irradiates the plate with visible light vertically (diffuse reflected light detection method) or obliquely (direct reflected light detection method) to detect changes in the reflected light. The method of detection is adopted, and in the case of a transparent register mark, there are the following two methods and the like.

That is, one is Japanese Patent Publication No. 1-28575.
Which is described in Japanese Patent Application Laid-Open No. 1-283147, in which a register mark printed with a transparent ink containing a trace amount of a fluorescent whitening agent is irradiated with ultraviolet rays to cause luminescence to be detected. This is a method in which a register mark printed by adding an ultraviolet absorbing substance to transparent ink is irradiated with ultraviolet rays, and the register mark is detected from the change in the amount of reflected or transmitted light due to the absorption of ultraviolet rays.

[0005]

When the apparatus is constructed by the above-mentioned conventional method, a dedicated apparatus is constructed for the transparent web and the opaque web, and a dedicated apparatus is constructed for the visible registration mark and the transparent registration mark. Therefore, there was a problem that the sensor head had to be replaced for each item.

Further, when the printing material is paper or the like and the surface is uneven, the light to be received is diffusely reflected, so that the S / N
The ratio decreases and it is difficult to detect with weak light. Also,
If the printing speed is increased, the printing material may flutter and the same problem as described above may occur. On the other hand, since the luminescence emission amount and the ultraviolet absorption amount are proportional to the intensity of the radiated ultraviolet light, the intensity of the radiated ultraviolet light must be increased to obtain the luminescence amount required for detection. However, if a high-intensity ultraviolet light source such as a xenon lamp or a mercury-xenon lamp is used as a light source, there is a problem that the ink is ignited due to heat generation.

Further, if both an ultraviolet light source and a visible light source are prepared in order to cope with the type of ink, it is necessary to incorporate these light sources into the detection unit in order to irradiate the register mark with these lights, and the detection unit There is no choice but to increase the size.

Further, in the case of a transparent dragonfly, it is necessary to mix a fluorescent agent or the like into the dragonfly, which is not preferable in food-related products and arts. In addition, it was impossible to detect if the web itself contained a fluorescent agent or the like.

The present invention has been made under the above circumstances, and an object of the present invention is to use a fluorescent whitening agent, an ultraviolet absorber or the like for register marks printed with any ink on any web. It is an object of the present invention to provide a registration method in printing and an apparatus for the same, in which the registration of the printing can be performed by detecting the registration mark and controlling the interval between the registration marks without any need.

[0010]

SUMMARY OF THE INVENTION The present invention detects a plurality of register marks printed on a web, controls the positional relationship between the register marks, and adjusts the registration of printing. The above object of the present invention is to print a register mark on each of a plurality of plates, detect each of the register marks by a plurality of detecting means arranged at a predetermined interval, and detect the positional relationship. In the registration method for controlling the distance between the registration marks to perform printing registration, a fiber unit capable of bidirectionally transmitting visible light and ultraviolet rays by a plurality of optical fibers is used as the detection means, and Using a detection head having a plurality of attachment members capable of attaching and detaching the fiber terminals of the optical fiber so that irradiation and light reception can be performed at a plurality of angles. Depending on the type of ink and the type of ink of the register mark, either the visible light or the ultraviolet light is selected, and the mounting position of the optical fiber for transmitting the selected light to the detection head is appropriately selected to register the register mark. Is achieved by detecting the position of In addition, a high-intensity ultraviolet light source, a fiber unit capable of bidirectionally transmitting light from the high-intensity ultraviolet light source through a plurality of optical fibers, and irradiation and light reception at multiple angles with respect to a plate on which a register mark is printed. There are two sets of a plurality of attachment members capable of attaching and detaching the fiber terminals of the optical fiber at predetermined intervals as much as possible, and the first and the first for detecting the register mark together with the optical fiber to be inserted. 2, a detection head that constitutes the detection means, and a filtering means that extracts visible light and ultraviolet light from the light from the high-intensity ultraviolet light source at any position on the optical path from the high-intensity ultraviolet light source to the plate. By recognizing the positional relationship of a plurality of register marks based on the reflected light from the plate introduced through the optical fibers of the first and second detecting means and controlling the intervals, It is achieved by a control means for performing combined.

[0011]

According to the present invention, a fiber unit capable of bidirectionally transmitting visible light and ultraviolet rays by a plurality of optical fibers is provided as a plurality of detecting means arranged at a predetermined interval to detect a register mark. In contrast, a detection head that has two sets of mounting members that can attach and detach the fiber terminals of the optical fiber so that irradiation and light reception can be performed at multiple angles, is used according to the type of plate and the type of ink on the register mark. By selecting either visible light or ultraviolet light and the mounting position of the optical fiber that transmits the selected light to the detection head and detecting the position of the register mark. The position of the register mark can be detected regardless of whether it is a transparent register mark or a visible register mark.

[0012]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a view showing the schematic arrangement of an embodiment of a registration apparatus for printing according to the present invention. In the figure, two registration marks 16 printed on the web 15
And 16 'are irradiated with ultraviolet rays or visible light from the detection head 12 having built-in optical means, and the reflected light or emitted light is again received by the light receiving portion of the detection head 12. The obtained optical information is sent to the control unit 22 having a photoelectric conversion unit, a power supply and a light source through the fiber unit 6, converted into an electric signal and sent to the control unit 23 by the shielded wire 24.
The control unit 23 controls a compensator roller (not shown) of the printing machine on the basis of the inputted electric signal to perform printing registration. The control unit 22 and the control unit 23 may be housed in the same box, and the mounting method of the detection head 12 can be changed appropriately.

FIG. 2 is a diagram showing an example of a means for separating visible light and ultraviolet light from one light source. Light emitted from a light intensity ultraviolet light source 1 such as a xenon lamp or a mercury xenon lamp is collected by lenses 4 and 4 '. Visible light and ultraviolet light are obtained by passing light through the UV reject filter 2 and the band pass filter 3, respectively.

FIG. 3 is a view showing the outer shape of a fiber unit composed of an optical fiber. Fiber unit 6
The control unit side terminal comprises a visible light input terminal 8 of the optical fiber 7, an ultraviolet ray input terminal 9 and signal output terminals 10 and 11 from the first and second detecting means, and the detection head side terminal of the fiber unit 6. Are output terminals 8 ', 8 "and 9', 9" obtained by dividing a fiber into which visible light and ultraviolet light are input, and signal input terminals 10 ', 11' from the first and second detecting means. Consists of. Here, the optical fiber 7
As a material for the above, a normal glass fiber may be used for visible light, but a single-component quartz fiber is used for ultraviolet light. A single component quartz fiber is also used for the light receiving fiber.

FIG. 4 is a vertical sectional view of the detection head, FIG. 5 is a plan view thereof, and FIG. 6 is a side view thereof. The main body of the detection head 12 is a light-shielding box 13 in order to prevent the detection means from being affected by visible disturbance light, and a quartz glass window 14 is opened on the lower surface facing a web 15 such as paper or film.
Further, on the upper surface thereof, there are clasps 31, 31 ', 3 for detachably connecting the detection head side terminals of the fiber unit 6.
2, 32 ', 33, 33', 34, 34 'and 35, 3
5'is attached at different positions and angles. However, the clasps 33 and 33 'are for spare use, and the unused fiber terminals are retained. The light-blocking box 13 has optical means 21 for assisting the projection or reception of light from each of the connected fiber terminals.
Is built in. Further, a reflection plate 17 which is necessary for a transparent printing material is placed at a position where the quartz glass window 14 faces the web 15. The distance between the two detection means formed in the detection head is 20 mm.

The possible detection methods for each of the visible register marks and transparent register marks printed on the transparent web, and the visible register marks and transparent register marks printed on the opaque web will be listed below. For the sake of convenience, V
R and ultraviolet light are expressed as UV.

First, in the case of a visible register mark printed on a transparent web, the detectable combinations of (irradiation light-detection light) are (VR-VR) and (UV-UV). (VR-
VR) is a conventional method for detecting the amount of visible light absorption and reflection. (UV-UV) is originally for detecting a transparent register mark to which an ultraviolet absorber is added, but it is also possible to detect a visible register mark. In the case of a transparent dragonfly to which an ultraviolet absorber or the like printed on a transparent web is added, the detectable combination is (UV-
UV) and (UV-VR). (UV-UV) is the case of a transparent dragonfly to which an ultraviolet absorber is added, and the ultraviolet ray is absorbed when it is irradiated, so it can be detected by the amount of the ultraviolet ray from the reflection plate 17. (UV-VR) is a case of a transparent dragonfly to which a fluorescent emitting agent has been added, and it emits luminescence when irradiated with ultraviolet rays, and therefore such a dragonfly can be detected by detecting it in the visible region.

For visible registration marks printed on an opaque web, the detectable (illumination light-detection light) combination is (VR-VR). (VR-VR) is a conventional method for detecting the amount of visible light absorption and reflection. In the case of a transparent dragonfly to which an ultraviolet absorber or the like printed on an opaque web is added, it is the same as in the case of a transparent web, depending on the ultraviolet absorber or fluorescent luminescent agent (UV-UV) or (UV-VR). You can do it.

In the case of a transparent dragonfly (or an opaque web containing a fluorescent agent) printed on the opaque web without addition of an ultraviolet absorber or the like, the detectable combinations are (VR-VR) and (UV-UV). Is. Even if the transparent register mark does not have an ultraviolet absorber added, if the register mark has a reflectance higher than the reflectivity of the opaque web, the intensity of the reflected light through the register will be higher than the intensity of the reflected light on the opaque web. I will use it because it will be bigger. At this time, if the visible light is irradiated at an angle of 20 to 40 degrees and the specularly reflected light is observed, the transparent register mark on the opaque web can be detected by its intensity. Therefore, in this case, the positions of the clasps 31, 31 'and 35, 35' may be used in the detection head 12 shown in FIG.

As described above, if individual detection is possible, it is possible to register each plate in any combination. For example, when comparing the register of the plate printed with the transparent ink added with the ultraviolet absorber and the plate printed with the visible ink, the ultraviolet output terminal 9 ′ or 9 ″ of the fiber unit 6 is attached to the clasp 32. , And the register mark signal input terminal 10 'is inserted into the clasp 34 to form the first detecting means. Similarly, the visible light output terminal 8'or 8 "is fitted into the clasp 32', and the register mark is also inserted. Signal input terminal 11 '
May be inserted into the clasp 34 'to serve as the second detecting means. Further, when comparing the register of the plate printed with the transparent ink to which the ultraviolet absorber is not added and the plate printed with the visible ink, the visible light output terminal 8 ′ of the fiber unit 6 is clamped 31 , And the register mark signal input terminal 10 ′ is inserted into the clasp 35 as the first detecting means, the visible light output terminal 8 ″ is fitted into the clasp 32 ′, and the register mark signal input terminal 11 ′. May be inserted into the clasp 34 'to serve as the second detecting means.Some examples of combinations are shown in FIGS. 7 (A) to (C) and 8 (A) to (D).

Now, assuming that the web 15 on which the visible register marks 16 and the transparent register marks 16 'are printed at a distance of 20 mm is conveyed in the direction of the arrow shown in FIG. 6, the first detecting means and the second detecting means. Register mark signal input terminal 10 '
The optical signals shown in FIGS. 9A and 9B are input to 11 and 11 ', respectively. In the figure, the vertical axis represents the light intensity and the horizontal axis represents the elapsed time. Here, a and a'represent a decrease in the light amount due to the light absorption of the visible registration mark, and b represents a decrease in the light amount due to the light absorption of the transmission mark. Since the distance between the first and second detecting means is 20 mm, if the distance between the visible registration mark 16 and the transparent registration mark 16 'is exactly 20 mm, b and a'will be at the same time (broken line C).
Appear in (above). If b is off line C, then 2
Since the displacement of one print is detected as a time difference, the value of the displacement can be obtained from the transport speed. These signal processing is performed by the fiber unit 6 by the control unit 22.
The optical signal transmitted to the electric signal is converted into an electric signal by the photoelectric element, and the compensator roller is controlled by the control unit 23 based on the obtained positional deviation value, thereby registering the patterns printed with the two inks. Can be done.

Here, in the case of FIG. 9 described above, light is absorbed in the register mark portion, the light amount is reduced and the waveform becomes a downward rectangular wave. For example, a transparent register mark having a high reflectance on an opaque web is used. When the amount of light increases at the register mark, such as when detecting by regular reflection, an upward rectangular wave is generated. In some cases, only a, a ′, only b, or both of them face upward. Therefore, all the waveforms are aligned downward by turning them on and off using an inverting circuit in accordance with those cases. This allows uniform processing in any case.

By the way, FIG. 2 shows an example of means for separating visible light and ultraviolet light from one light source, but the invention is not limited to this. Hereinafter, some other aspects will be shown.
FIG. 10A shows a mode in which the visible light filter 61 and the ultraviolet filter 62 are embedded in the connection terminal of the fiber unit 6 '. In this case, the control unit 22 outputs visible light,
The light including both ultraviolet rays is extracted, and in the embedded filters 61 and 62, only the visible light or only the ultraviolet rays is changed thereafter by the filters 61 and 62. In addition, FIG. 2B shows a visible light filter 61 and an ultraviolet filter 6 at the connection terminal of the fiber unit 6 ″.
2 shows a detachable / replaceable type and a mode in which the visible light filter 61 and the ultraviolet filter 62 are cap / replaceable at the irradiation end of the fiber unit 6 ″.

Further, FIG. 11A shows a mode in which a filter is fitted in the detection head 12 and arranged. Further, the size of the control unit 22 is not limited, and if it is not necessary to use one light source, it is necessary to provide two ultraviolet light sources 221 and two visible light sources 222 as shown in FIG. Therefore, it is possible to irradiate all of them, and a method of switching with a switch or the like may be used. Alternatively, the light source may be unitized and replaceable as shown in FIG.

On the other hand, as the light receiving method by the sensor, a sensor having a spectral sensitivity characteristic from the visible region to the ultraviolet region is adopted, and the detection is performed by the attenuation of the received light intensity of each region even if the light source is changed. There is a method in which both a sensor for visible light and a sensor for ultraviolet light are provided in advance, and switching is performed according to the light source, a method of replacing the sensor itself in the control unit 22, and the like.

Finally, the principle and the condition that a transparent register mark or the like containing no ultraviolet absorber can be detected by specular reflection light will be described. 12A and 12B are diagrams for explaining the principle and the condition thereof. Here, the intensity of the irradiation light from the light source is I, the reflectance of the opaque web 82 is R _p , and the reflectance of the register mark 83 is R _i , the light when the incident light on the register mark 83 is transmitted from the upper surface to the lower surface thereof. Let the absorption rate be α. Therefore, first, when the light is reflected on the opaque web 82 as shown in FIG.
_p × I. Next, as shown in FIG.
In the case of reflection above, the intensity at each point on the optical path is as shown in the figure, and the intensity (up to the second order) of the reflected light is {(1-R _i ) × (1-R _p ) × R _p × α ² + R
_i } × I. Further, the difference F between the intensity of the reflected light on the register mark 83 and the intensity of the reflected light on the opaque web 82 is as shown in Formula 1.

[0027]

## EQU1 ## F = {(1-R _i ) × (1-R _p ) × R _p × α ² + R _i } × I-R _p × I = {(1-R _i ) × (1-R _p ) × R _p × α ² + (R _i −R _p )} × I In the formula 1, (1-R _i ), (1-R _p ), R _p , α
^Since all ² are positive, the difference F is always positive if the condition R _i ≧ R _p is satisfied. That is, R _i ≧ R
_If the condition of _p is satisfied, the opaque web 82
The intensity of the reflected light on the register mark 83 is higher than the intensity of the reflected light on the above. Therefore, if the condition of R _i ≧ R _p is satisfied, the registration mark 83 can be identified by the change by observing the reflected light. At this time, R _i and R
_The larger the difference in _p, the easier the identification.

Regarding the irradiation angle, the smaller the angle formed by the opaque web 82 and the irradiation light is, the better the detection sensitivity is, which is preferable in view of physical theory. Therefore, the angle is preferably 20 to 40 degrees, and the best angle is about 30 degrees. .

[0029]

As described above, according to the registration method and apparatus for printing of the present invention, switching is performed by using a filtering means for a high-intensity ultraviolet light source or by preparing a visible light source and an ultraviolet light source. By using the means, multiple visible lights and ultraviolet rays are taken out by the optical fiber, and the register mark printed with any ink on any web can be detected by attaching or detaching the optical fiber, so it is printed on each plate. The registration marks of each plate can be detected by appropriately combining and irradiating the registration marks according to the type of the registration marks, and the interval between them can be controlled to match the registration of printing. In particular, even a register mark printed with a transparent ink that does not contain an ultraviolet absorber can be detected as total reflected light by adopting a configuration in which each irradiation degree can be selected. Moreover, since an optical fiber is used for transmission and irradiation, a high-intensity ultraviolet light source can be used, and in that case, there is an advantage that the device becomes compact.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of an embodiment of a registration device for printing according to the present invention.

FIG. 2 is a diagram showing an example of means for separating visible light and ultraviolet light from one light source.

FIG. 3 is a diagram showing an outer shape of a fiber unit including an optical fiber.

FIG. 4 is a vertical cross-sectional view of the detection head 12.

FIG. 5 is a plan view of the detection head 12.

FIG. 6 is a side view of the detection head 12.

FIG. 7 is a diagram showing an example of a combination of irradiation light and detection light for each register mark of each plate.

FIG. 8 is a diagram showing an example of a combination of irradiation light and detection light for each register mark of each plate.

FIG. 9 is a diagram showing an optical signal output from the detection head.

FIG. 10 is a diagram showing another example of means for separating visible light and ultraviolet light from one light source.

FIG. 11 is a diagram showing another example of means for separating visible light and ultraviolet light from one light source, and an example of switching between the visible light source and the ultraviolet light source.

FIG. 12 is a diagram for explaining the principle and conditions under which a register mark of transparent ink containing no ultraviolet absorber or the like can be detected.

[Explanation of symbols]

 1 high-intensity ultraviolet light source 2 UV reject filter 3 bandpass filter 6 fiber unit 7 optical fiber 8 visible light input terminal 8'visible light output terminal 9 ultraviolet light input terminal 9'ultraviolet light output terminal 10 register mark signal output terminal 10 'register mark signal Input terminal 11 Register mark signal output terminal 11 'Register mark signal input terminal 12 Detection head 13 Shading box 14 Quartz glass window 15 Web 16 Register mark 22 Control section 23 Control section 31 Fastener 32 Fastener 33 Fastener 34 Fastener 35 Fastener Tool 61 Visible light filter 62 Ultraviolet filter

Claims (4)

[Claims] 1. A register mark is printed on each of a plurality of plates, each of the register marks is detected by a plurality of detecting means arranged at a predetermined interval, and the register mark interval is determined based on the positional relationship. In the registration method of controlling registration of printing, a fiber unit capable of bidirectionally transmitting visible light and ultraviolet rays by a plurality of optical fibers as the detecting means, and irradiating the plate at a plurality of angles. A detection head having two sets of a plurality of mounting members to which the fiber terminals of the optical fiber can be attached and detached so as to be able to receive light is used, and visible light or ultraviolet light is used depending on the type of the plate and the type of ink of the register mark. And detecting the position of the register mark by appropriately selecting the mounting position of the optical fiber transmitting the selected light to the detection head. Registration method for printing. 2. In the case of a register mark printed on the opaque plate without containing an ultraviolet absorber or the like, visible light is selected and the mounting position at which the irradiation angle is 20 to 40 degrees is selected. The registering method for printing according to claim 1, wherein. 3. A high-intensity ultraviolet light source, a fiber unit capable of bidirectionally transmitting light from the high-intensity ultraviolet light source through a plurality of optical fibers, and a plate on which a register mark is printed, is irradiated at a plurality of angles. .A plurality of mounting members to which the fiber terminals of the optical fiber can be attached / detached so as to be able to receive light are provided at predetermined intervals, and a first member for detecting the register mark together with the optical fiber to be inserted. A detection head that constitutes the first and second detection means, and at any position on the optical path from the high-intensity ultraviolet light source to the plate,
A plurality of filtering means for extracting visible light and ultraviolet light from the light emitted from the high-intensity ultraviolet light source, and a plurality of reflected light from the plate introduced through the respective optical fibers of the first and second detecting means. A registration device for printing, comprising: a control unit that performs registration by recognizing the positional relationship of the registration marks and controlling the distance therebetween. 4. The registration device for printing according to claim 1, wherein a visible light source, an ultraviolet light source, and a switching means for these are provided in place of the high-intensity ultraviolet light source and the filtering means.