JP3120554B2 - Registration method and apparatus for printing - Google Patents

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 detecting a plurality of register marks printed on a web and controlling the positional relationship between the marks to register the print marks. It is.

[0002]

2. Description of the Related Art As a method of registering in printing, there are the following methods.
2. Description of the Related Art A method of printing a register mark for each plate and controlling the positional relationship between the register marks has been widely used. Therefore, conventionally, a method of visually identifying and controlling the mutual positional relationship between the register marks has been adopted. Here, the register mark is printed with visible ink (visible mark)
And printed with transparent ink (transparent register marks).
In particular, when a transparent register mark is visually detected, the operation is performed under a low speed operation using an ultraviolet lamp.

Recently, a method of compensating for printing misalignment by detecting registration marks with an optical sensor and comparing the positions with each other has become widespread. Here, in the case of a visible register mark, the visible light source irradiates the plate vertically (diffuse reflection light detection method) or obliquely (direct reflection light detection method) with a visible light to capture the change in the reflected light. A method of detection is employed. In the case of a transparent registration mark, there are the following two methods.

That is, one is Japanese Patent Publication No. 27857/1990.
And a method of irradiating a registration mark printed with a transparent ink containing a trace amount of a fluorescent whitening agent with ultraviolet rays to emit luminescence and detecting the same, and the other method is described in JP-A-1-283147. In this method, a register mark printed by adding an ultraviolet absorbing substance to transparent ink is irradiated with ultraviolet light, and the register mark is detected from a change in the amount of reflection or transmission due to absorption of ultraviolet light.

[0005]

By the way, when the apparatus is constructed by the above-mentioned conventional method, a dedicated apparatus is constructed for each of the transparent web and the opaque web, and for the visible register mark and the transparent register mark. Therefore, there is a problem that the sensor head must be replaced for each item.

When the printing material has irregularities on the surface such as paper, the light to be received is irregularly reflected.
The ratio decreases and it is difficult to detect with weak light. Also,
When the printing speed is increased, the same problem as described above occurs because the printing material flaps. On the other hand, the amount of luminescence and the amount of ultraviolet absorption are proportional to the intensity of the irradiated ultraviolet light, so that the intensity of the irradiated ultraviolet light must be increased to obtain the amount of light 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, problems such as firing of the ink due to heat generation occur.

Further, if both an ultraviolet light source and a visible light source are prepared in order to cope with the type of ink, it becomes necessary to incorporate these light sources into a detection unit in order to irradiate the register mark with these lights. It has to be enlarged.

Further, in the case of a transparent register mark, a fluorescent agent or the like must be mixed into the register mark, which is not preferable in foods and arts. In addition, it was not detectable when the web itself contained a fluorescent agent or the like.

SUMMARY OF THE INVENTION The present invention has been made under the above circumstances, and an object of the present invention is to use a fluorescent brightener or an ultraviolet absorber for register marks printed on any web with any ink. It is an object of the present invention to provide a register method and an apparatus for printing that can detect without detection and control the interval between register marks to register the print.

[0010]

SUMMARY OF THE INVENTION According to the present invention, there is provided a method and apparatus for registering a print in which a plurality of register marks printed on a web are detected and the positional relationship between the marks is controlled to register the print. SUMMARY OF THE INVENTION The object of the present invention is to provide a transparent and opaque plate with a visible mark.
Printing with opaque ink, a plurality of detecting means arranged at predetermined intervals, each of the register marks is detected, and the registration mark is controlled by controlling the interval between the register marks based on the positional relationship. In the registering method, a fiber unit capable of transmitting visible light and ultraviolet light bidirectionally by a plurality of optical fibers as the detection means,
A plurality of fasteners capable of attaching and detaching a fiber terminal of the optical fiber so as to be capable of irradiating and receiving light at a plurality of angles with respect to the plate are used as first and second detection means at predetermined intervals.
Using two sets of detection heads, selecting either visible light or ultraviolet light in accordance with the type of the plate and the type of ink of the register mark, and the detection head of the optical fiber transmitting the selected light . The position of the register mark is detected by appropriately selecting the position of attachment to the fastener , and the transparent opaque plate does not contain an ultraviolet absorber or the like.
In the case of a register mark printed by
And the irradiation angle is set from 20 degrees to 40 degrees.
Select the fastener, insert the fiber terminal, and
This is achieved by capturing specularly reflected light of visual light. In addition, a high-intensity ultraviolet light source, a fiber unit capable of transmitting light from the high-intensity ultraviolet light source in two directions through a plurality of optical fibers, and a register mark made of visible ink or opaque ink.
The printed, transparent, opaque plate has two sets of a plurality of fasteners at a predetermined interval to which the fiber terminal of the optical fiber can be attached and detached so that irradiation and light reception can be performed at a plurality of angles, a detection head constituting a first and second detection means for detecting the register mark with the optical fiber terminals fitted, provided from the high intensity ultraviolet light source on the light path up to the plate, the high A plurality of register marks based on reflected light from the plate introduced through respective optical fibers of the first and second detecting means, and a filtering means for extracting visible light and ultraviolet light from light emitted by the luminance ultraviolet light source; Control means for recognizing the positional relationship between the detection heads and controlling the intervals thereof to perform registration.
Fastener with irradiation angle set from 20 degrees to 40 degrees
With a UV absorber etc. on the opaque plate
Detection of register marks printed with transparent ink that does not contain
At this time, a fiber terminal is inserted and the specular reflected light of visible light is
Is achieved by

[0011]

According to the present invention, a fiber unit capable of transmitting visible light and ultraviolet light in two directions by a plurality of optical fibers is provided as a plurality of detecting means arranged at predetermined intervals to detect a register mark . Specular reflection on opaque plate
Using a detection head having two sets of a plurality of fasteners at a predetermined interval that can attach and detach the fiber terminal of the optical fiber so that irradiation and light reception can be performed at a plurality of angles that can be taken,
Select either visible light or ultraviolet light in accordance with the type of plate and the type of ink of the register mark, and select the position of the optical fiber that transmits the selected light to the detection head as appropriate to the position of the register mark. Is detected, the position of the register mark can be detected regardless of the transparent web or the opaque web, or regardless of the transparent register mark or the visible register mark.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of an embodiment of a register apparatus in printing according to the present invention. In the figure, two registration marks 16 printed on a web 15
And 16 ′ are irradiated with ultraviolet light or visible light from the detection head 12 having a built-in optical means, and the reflected light or light emission is received again 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 shield line 24.
The control unit 23 controls a compensator roller (not shown) of the printing press on the basis of the input electric signal to register printing. Note that the control unit 22 and the control unit 23 may be housed in the same box, and the method of mounting the detection head 12 may be changed as appropriate.

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 '. The light is emitted, and the direction is changed by a mirror 5 as necessary, and the light is passed through a UV reject filter 2 and a band pass filter 3 to obtain visible light and ultraviolet light, respectively.

FIG. 3 is a diagram showing an outer shape of a fiber unit composed of optical fibers. Fiber unit 6
The control unit side terminal comprises a visible light input terminal 8, an ultraviolet light input terminal 9 of the optical fiber 7, and signal output terminals 10 and 11 from the first and second detection means, and a 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, respectively, 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 light source, 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 as the light receiving fiber.

FIG. 4 is a longitudinal 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.
On its upper surface, clasps 31, 31 'and 3 for detachably connecting the detection head side terminal of the fiber unit 6 are provided.
2, 32 ', 33, 33', 34, 34 'and 35, 3
5 'is provided at different positions and angles. However, the clasps 33 and 33 'are reserved, and unused fiber terminals are retained. The light shielding box 13 includes an optical unit 21 for assisting light emission or light reception of each connected fiber terminal.
Is built-in. Further, a reflection plate 17 necessary for a transparent printing material is placed at a position opposite to the quartz glass window 14 with respect to the web 15. The interval between the two detection means formed in the detection head is 20 mm.

In the following, possible detection methods are listed for each of the visible registration marks and the transparent registration marks printed on the transparent web, and for the visible registration marks and the transparent registration marks printed on the opaque web, respectively. For convenience, the visible light is V
R and ultraviolet light are expressed as UV.

First, in the case of a visible registration mark printed on a transparent web, a detectable (irradiation light-detection light) combination is (VR-VR) and (UV-UV). (VR-
VR) is a conventional method for detecting the amount of visible light absorption and reflection. (UV-UV) is intended to detect 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 registration mark to which an ultraviolet absorber or the like is added, which is printed on a transparent web, the detectable combination is (UV-
UV) and (UV-VR). (UV-UV) is a transparent register mark to which an ultraviolet absorber is added, and when irradiated with this, the ultraviolet ray is absorbed, so that it can be detected by the amount of the ultraviolet ray from the reflector 17. (UV-VR) is a transparent registration mark to which a fluorescent luminescent agent is added. When ultraviolet rays are irradiated, luminescence is emitted, and such a registration mark can be detected by detecting in the visible region.

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

In the case of a transparent dragonfly (or an opaque web containing a fluorescent agent) to which no ultraviolet absorber or the like is added, which is printed on the opaque web, the combinations that can be detected are (VR-VR) and (VR-VR). UV-UV). Even if no ultraviolet absorber or the like is added to the transparent register mark, if the register mark has a reflectance higher than that of the opaque web,
Since the intensity of the reflected light via the register mark is always higher than the intensity of the reflected light on the opaque web, it is used. At this time, by irradiating visible light at an angle of 20 to 40 degrees and observing the specular reflection light, the transparent register mark on the opaque web can be detected based on the 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, any combination can be registered for each plate as long as it can be detected individually. For example, when comparing the registration between the plate printed with the transparent ink to which the ultraviolet absorbent is added and the plate printed with the visible ink, the ultraviolet output terminal 9 ′ or 9 ″ of the fiber unit 6 is connected to the clasp 32. And the register mark signal input terminal 10 'is inserted into the clasp 34 as a first detecting means. Similarly, the visible light output terminal 8' or 8 "is inserted into the clasp 32 '. Signal input terminal 11 '
May be inserted into the clasp 34 'to serve as the second detecting means. Further, when comparing the registration between the plate printed with the transparent ink to which no ultraviolet absorber or the like is 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 a first detecting means, the visible light output terminal 8 "is inserted into the clasp 32', and the register mark signal input terminal 11 '. 7A to 7C and FIGS. 8A to 8D show some examples of combinations.

Now, assuming that the web 15 on which the visible register marks 16 and the transparent register marks 16 'are printed at intervals 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 '
And 11 'are input with the optical signals shown in FIGS. The vertical axis in the figure represents the light amount, and the horizontal axis represents the elapsed time. Here, a and a 'represent a decrease in light amount due to light absorption of visible registration marks, and b represents a decrease in light amount due to light absorption of transmission registration marks. Since the distance between the first and second detection means is set to 20 mm, if the distance between the visible register mark 16 and the transparent register mark 16 ′ is exactly 20 mm, b and a ′ are at the same time (broken line C).
Above). If b is off line C, 2
Since the shift between the two prints is detected as a time difference, the value of the positional shift can be obtained from the transport speed. These signal processes are performed by the control unit 22 by the fiber unit 6.
The optical signal transmitted to the device is converted into an electric signal by a photoelectric element, and the compensator roller is controlled by the control unit 23 based on the obtained position shift value, thereby registering the pattern printed with the two inks. Can be performed.

Here, in the case of FIG. 9 described above, light absorption occurs at the part of the register mark, the amount of light decreases, and the waveform becomes a downward rectangular wave. For example, a transparent register mark having a high reflectance on an opaque web is used. In the case where the light amount increases at the register mark portion as in the case of detection by regular reflection, an upward rectangular wave is formed. Only a, a ', only b, or any of them may face upward. Therefore, according to those cases, the waveforms are all aligned downward by turning on / off the inverting circuit. Thereby, the processing can be performed uniformly in any case.

FIG. 2 shows an example of the means for separating visible light and ultraviolet light from one light source, but the present invention is not limited to this. Hereinafter, some other embodiments will be described.
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, visible light,
Light containing both ultraviolet rays is extracted, and the filters 61 and 62 in the embedded filters 61 and 62 thereafter convert only visible light or only ultraviolet rays. FIG. 4B shows the visible light filter 61 and the ultraviolet filter 6 at the connection terminal of the fiber unit 6 ″.
2 shows a configuration in which the detachable / replaceable type 2 is used, and a mode in which the visible light filter 61 and the ultraviolet filter 62 are cap / replaceable type at the irradiation end of the fiber unit 6 ″.

FIG. 11A shows a mode in which the filter is arranged in the detection head 12 in a fitting manner. Further, if there is no limitation on the size of the control unit 22 and it is not always necessary to use one light source, as shown in FIG. 3B, two ultraviolet light sources 221 and two visible light sources 222 are provided, and the half mirror 223 is provided. May be configured to enable irradiation, and a method of switching with a switch or the like may be used. Further, as shown in FIG. 3C, the light source may be configured as a unit so as to be replaceable.

On the other hand, as a light receiving system by the sensor, a sensor having a spectral sensitivity characteristic from the visible region to the ultraviolet region is employed, and even if the light source changes, detection is performed by attenuating the received light intensity in each region. There is a method of providing both a sensor for visible light and a sensor for ultraviolet light, and switching according to the light source, a method of replacing the sensor itself in the control unit 22, and the like.

Finally, the principle and conditions for the fact that a transparent register mark or the like containing no ultraviolet absorbent or the like can be detected by regular reflection light will be described. FIGS. 12A and 12B are diagrams for explaining the principle and the conditions. Here, the intensity of the irradiation light from the light source is I, the reflectance of the opaque web 82 is R _p , the reflectance of the registration mark 83 is R _i, and the light incident on the registration mark 83 is transmitted from the upper surface to the lower surface. Let the absorption rate be α. Therefore, 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 on the upper side, 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 Expression 1.

[0027]

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 where (1-R _i ), (1-R _p ), R _p , α
^{Since 2} is all positive, the difference F is always positive if the condition of R _i ≧ R _p is satisfied. That is, R _i ≧ R
_If the condition _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 upper side. Therefore, if the condition of R _i ≧ R _p is satisfied, it is possible to identify the registration marks 83 by observing the reflected light and observing the change. At this time, R _i and R
_The greater the difference in _p, the easier it is to identify.

With respect to the irradiation angle, it is preferable in terms of physical theory that the smaller the angle between the opaque web 82 and the irradiation light is, the higher the detection sensitivity is. However, if the angle is too small, the influence of the flapping of the opaque web 82 appears. Therefore, the angle is desirably 20 to 40 degrees, and most preferably about 30 degrees. .

[0029]

As described above, according to the registering method and apparatus for printing according to 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, a plurality of visible light and ultraviolet light are taken out by an optical fiber, and by attaching and detaching and replacing the optical fiber, it is possible to detect the register mark printed with any ink on any web, so that it is printed on each plate. By appropriately irradiating the registration marks depending on the type of the registration marks, the registration marks of each plate can be detected, and the interval between them can be controlled to adjust the registration of the printing. In particular, even for register marks printed with transparent ink that does not contain ultraviolet absorbers, etc., detection is possible by capturing the total reflected light by adopting a configuration in which the irradiation angle can be selected. Becomes Further, 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 apparatus becomes compact.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of an embodiment of a register apparatus in printing according to the present invention.

FIG. 2 is a diagram illustrating an example of a unit that separates visible light and ultraviolet light from one light source.

FIG. 3 is a diagram showing an outer shape of a fiber unit constituted by optical fibers.

FIG. 4 is a longitudinal sectional view of the detection head 12.

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

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

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

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

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

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

FIG. 11 is a diagram illustrating another example of a unit that separates visible light and ultraviolet light from one light source, and an example of switching between a visible light source and an ultraviolet light source.

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

[Explanation of symbols]

 REFERENCE SIGNS LIST 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 input terminal 9 ′ ultraviolet 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 Light shielding box 14 Quartz glass window 15 Web 16 Register mark 22 Control unit 23 Control unit 31 Fastener 32 Fastener 33 Fastener 34 Fastener 35 Fastener Tool 61 Visible light filter 62 UV filter

Claims (3)

(57) [Claims] 1. A register mark is visible on a transparent or opaque plate.
Printing with opaque ink, a plurality of detection means arranged at predetermined intervals to detect each of the register marks, and control the interval between the register marks based on the positional relationship to perform printing registration. In the registration method,
As the detection means, visible light by a plurality of optical fibers,
At predetermined intervals, a fiber unit capable of transmitting ultraviolet light bidirectionally and a plurality of fasteners capable of attaching and detaching fiber terminals of the optical fiber so as to be able to irradiate and receive the plate at a plurality of angles are provided. A detection head having two sets is used as the first and second detection means, and either visible light or ultraviolet light is selected according to the type of the plate and the type of ink of the register mark, and the selected light is transmitted. by appropriately selecting the mounting position of the fastener of the detection head of the optical fiber so as to detect the position of the register mark to be, not
Transparent ink containing no UV absorber etc. in the transparent plate
For more printed register marks, select visible light.
And the irradiation angle is set from 20 degrees to 40 degrees
Select the fastener, insert the fiber terminal, and
A registration method for printing that captures specularly reflected light . 2. 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 ,
It has two sets of a plurality of fasteners at predetermined intervals to which the fiber terminals of the optical fiber can be attached and detached so that the transparent and opaque plates printed by ink can be irradiated and received at a plurality of angles. a detection head constituting a first and second detection means for detecting the register mark with the optical fiber terminals fitted, provided from the high intensity ultraviolet light source on the light path up to the plate, the Filtering means for extracting visible light and ultraviolet light from light from the high-intensity ultraviolet light source; and a plurality of registers based on reflected light from the plate introduced through the respective optical fibers of the first and second detecting means. Control means for recognizing the positional relationship between the marks and controlling the distance between the marks to perform foresight ,
Multiple fasteners have an irradiation angle set from 20 to 40 degrees
Fasteners, which have an opaque plate with UV absorption
Register marker printed with transparent ink that does not contain an absorbent
Insert a fiber terminal to detect
Register alignment apparatus in the print, characterized in that the so that seized Shako. 3. The registration apparatus according to claim 2 , further comprising a visible light source, an ultraviolet light source, and a switching unit for the visible light source and the ultraviolet light source, instead of the high-intensity ultraviolet light source and the filtering unit.