CN100503242C - Image forming method and ink-jet printing device - Google Patents

Abstract

An image forming method is provided for use with an ink-jet printing device which forms a dot on a recording medium by ejecting a drop of recording liquid. In the image forming method, an image in which a ground tint is embedded in one of a foreground part and a background part of an original image is formed, the ground tint indicating that copying of the original image is inhibited. A recording liquid adhesion area of the dot per unit area in the foreground part is made different from a recording liquid adhesion area of the dot per unit area in the background part.

Description

Formation method and ink jet printing device

Technical field

The present invention relates to be used for the formation method and the ink jet printing device of print image, wherein embed the shading (ground tint) that indication forbids copying original image.

Background technology

Routinely, various printed materials are arranged, it has forbids the original image that copies, and this comprises certificate, vital document or the like, for example residence card or family resister; And marketable securities, for example banknote, stock, bond or the like.In order to prevent that people have proposed several method and equipment to the unallowed unauthorised copies of the original image of this type of printed material, making it to discern the image that reproduces with the district office when reproduced image is the copy of original image.

For example, Japanese Laid-Open Patent Application discloses a kind of image processing equipment 2004-260341 number, and it comprises: the image assembled unit, and the picture pattern of copy targeting image is forbidden in this cells overlap and composite object image and indication; And the data output unit, the view data that this unit will obtain after composite object image and described picture pattern outputs to predetermined output equipment.

In addition, Japanese Laid-Open Patent Application also discloses a kind of image processing method 2004-260341 number, is used for the background parts and the sub-image part of differentiate between images.In this image processing method, the shading image generation unit generates the some set be used for the sub-image part represented with the pixel of first number, and the some set that is used for the background parts represented with the pixel of second number (this number is different from first number of pixels).In this way, generate new images.In this image processing method, the additional information cell basis is controlled at each position of the some group that comprises in the sub-image part of image corresponding to the bit value of the bit position of additional information.

In addition, use the paper that is called anti-forge paper, carry out special printing in advance for this paper.On this paper, with the optical density (OD) franking that can be reproduced by duplicator (for example character, as " forbidding copy "), it is the copy of original image that this mark is indicated the image of this paper.On the other hand, the background parts of the optical density (OD) print image that is difficult to reproduce with duplicator.Be equipped with the optical density (OD) of this mark part and background parts, make human eye be difficult to separator part and background parts.The mark part and the background parts that form in the zone of the file part that is different from image are called " shading ".

Requirement embeds shading and does not destroy information on the file as much as possible in document image, and burelage is for picking out its pattern for the copy of original image when the copy.And the printing to burelage is realized the method for for example using in laser printer by the photoelectricity Method of printing.

In recent years, people have not only extensively used the imaging device that uses the photoelectricity Method of printing, and extensively the imaging device (ink jet printing device) of inkjet printing methods (wherein use liquid discharge head as printhead, this printhead is discharged recording liquid (black agent)) is used in utilization.

Known ink jet printing device uses liquid discharge head as printhead.Liquid discharge head comprises: the pressure generation unit, and it generates the pressure to the black agent pressurization of liquid chamber, and liquid chamber is communicated with nozzle, and nozzle is discharged ink droplet.By drive the pressure generation unit of liquid discharge head according to image information, exert pressure to the black agent of liquid chamber.Discharge little ink droplet from nozzle, and make it be attached to recording medium, for example paper or film, thus on recording medium, form image (printing).

The point position that can form and some size and the diffusion of the point on recording medium are printed with inkjet printing methods and are printed with the photoelectricity Method of printing and different.That is,, can form a little on the position arbitrarily basically according to the photoelectricity Method of printing.But according to inkjet printing methods, the some position that printhead can form is subjected to the restriction of injector spacing and printhead driving frequency.

In addition, according to the photoelectricity Method of printing, the toner that is transferred to recording medium can not permeate recording medium.But,, after black agent is discharged to recording medium, prints liquid and can permeate recording medium, and can produce a diffusion according to inkjet printing methods.

Therefore, when using ink jet printing device (it is discharged little ink droplet and forms image (printing)) when printing, to have the problem that the picture pattern of copied files image is forbidden in indication of how printing.

Summary of the invention

One object of the present invention is to provide a kind of improved formation method, wherein can eliminate the problems referred to above.

Another object of the present invention is to provide a kind of, in described image, embed the shading that indication forbids copying original image by utilizing ink jet printing device to come the formation method of print image.

Another object of the present invention is to provide a kind of ink jet printing device of print image, in described image, embed the shading that indication forbids copying original image.

In order to achieve the above object, the invention provides a kind of formation method, be used on recording medium, forming a little ink jet printing device by discharging the record drop, this formation method may further comprise the steps: form wherein the image that embeds shading in the prospect part of original image and one of background parts, this shading is indicated and is forbidden copying original image; And make the record liquid bond area of putting on the unit are in the prospect part be different from the record liquid bond area of putting on the unit are in the background parts, wherein, carrying out shading prints, make described prospect part constitute by first set of neighbor point, described background parts is made of second set of neighbor point, and when described prospect part obtained described foreground portion and divides the enough black agent bond area of each required point by the black agent of described recording medium is soaked into, described prospect part constituted by the 3rd set of first set of described neighbor point being changed into by the given neighbor point that separates of counting.

Can dispose above-mentioned formation method, thereby a plurality of neighbor point constitutes shading.

Can dispose above-mentioned formation method, thereby, form a plurality of neighbor points that constitute shading by a plurality of record drops being discharged to the same position on the recording medium.

Can dispose above-mentioned formation method, thereby, change the record liquid bond area of putting on the unit are according to the light characteristic of the color of the record liquid that uses.

Can dispose above-mentioned formation method, thereby the record liquid bond area of putting on the unit are in the background parts is greater than the record liquid bond area of putting on the unit are in the prospect part.

Can dispose above-mentioned formation method, thereby the record liquid bond area of putting on the unit are in the prospect part is greater than the record liquid bond area of putting on the unit are in the background parts.

Can dispose above-mentioned formation method, thereby be equipped with the point of described ink jet printing device, and a plurality of neighbor point constitutes shading for formation variable-size on recording medium.

Can dispose above-mentioned formation method, thereby be equipped with the point of described ink jet printing device, and a plurality of neighbor point constitutes shading for formation fixed size on recording medium.

Can dispose above-mentioned formation method, thereby be equipped with the point of described ink jet printing device, and, form a plurality of neighbor points that constitute shading by a plurality of record drops being discharged to the same position on the recording medium for formation fixed size on recording medium.

In order to achieve the above object, the invention provides a kind of ink jet printing device, it forms on recording medium a little by discharging the record drop, this ink jet printing device comprises: the burelage creating unit, be used for forming wherein the image that embeds shading in the prospect part of original image and one of background parts, this shading is indicated and is forbidden copying original image; And control module, be used for making the record liquid bond area of putting on the unit are in the prospect part to be different from the record liquid bond area of putting on the unit are in the background parts, wherein, described ink jet printing device carries out shading and prints, make described prospect part constitute by first set of neighbor point, described background parts is made of second set of neighbor point, and when described prospect part obtained described foreground portion and divides the enough black agent bond area of each required point by the black agent of described recording medium is soaked into, described prospect part constituted by the 3rd set of first set of described neighbor point being changed into by the given neighbor point that separates of counting.

According to formation method of the present invention and ink jet printing device, when being equipped with ink jet printing device when on recording medium, forming the point of variable-size, form wherein the image that embeds shading in the prospect part of original image and one of background parts, this shading is indicated and is forbidden copying original image; And make the record liquid bond area of putting on the unit are in the prospect part be different from the record liquid bond area of putting on the unit are in the background parts.Perhaps when being equipped with ink jet printing device when forming the point of single fixed size on recording medium, a plurality of neighbor points constitute shadings.Perhaps,, form a plurality of neighbor points that constitute shading by a plurality of record drops being discharged to the same position on the recording medium when being equipped with ink jet printing device when on recording medium, forming the point of single fixed size.Correspondingly, can utilize this ink jet printing device, print and wherein to embed the image that indication forbids copying the shading of original image.

By detailed description, can know other purposes of the present invention, feature and advantage below in conjunction with accompanying drawing.

Description of drawings

Fig. 1 is the side view of the structure of the mechanical part that shows the ink jet printing device can form many-valued dot image.

Fig. 2 is the plane of the structure of the mechanical part of this ink jet printing device of demonstration.

Fig. 3 is the profile of demonstration along the structure of the liquid discharge head of liquid chamber longitudinal direction.

Fig. 4 is the profile of demonstration along the structure of the liquid discharge head of liquid chamber horizontal direction.

Fig. 5 is the block diagram of the structure of the control module of demonstration ink jet printing device.

Fig. 6 is the block diagram of the structure of a control module and head driver in the indicative control unit.

Fig. 7 is the diagram that is used for explaining the work of a control module and head driver.

Fig. 8 is the block diagram that shows the structure of the print system that comprises image processing equipment of the present invention and ink jet printing device.

Fig. 9 is the block diagram of the structure of display image treatment facility.

Figure 10 is the block diagram that is used for explaining the functional structure of image processing program in the print system.

Figure 11 is the block diagram that is used for explaining the functional structure of another image processing program in the print system.

Figure 12 is used for explaining the diagram that burelage is printed.

Figure 13 is used for explaining the diagram that another burelage is printed.

Figure 14 is used for explaining the diagram of dividing the effect that generates shading in the foreground portion of image.

Figure 15 is used for explaining the diagram that generates the effect of shading in the background parts of image.

Figure 16 is the diagram that is used for explaining according to the shading reproducibility of droplet size.

Figure 17 is the diagram that is used for explaining according to the shading reproducibility of droplet size.

Figure 18 is the diagram that is used for explaining the shading generation method of the point that utilizes tiny spot size.

Figure 19 (A) and Figure 19 (B) are the diagram of the example that is used for explaining tiny some set.

The specific embodiment

Referring now to accompanying drawing embodiments of the invention are described.

The example of the mechanical part of the ink jet printing device that can form many-valued point is described with reference to Fig. 1 and Fig. 2.Fig. 1 is the side view of the structure of the mechanical part of this ink jet printing device of demonstration.Fig. 2 is the plane of the structure of the mechanical part of this ink jet printing device of demonstration.

As Fig. 1 and shown in Figure 2, in this ink jet printing device, carriage 4 is by guide rod 2 and pillar 3 (it be across side plate 1A that constitutes framework 1 and the induction element of 1B) support, thereby carriage 4 can be mobile along main scanning direction (carriage moving direction).By main scan motor 5 by timing belt 7 (it twines between drive pulley 6A and slave tape pulley 6B) along movable support bracket 4 on the arrow indicated direction among Fig. 2.

Printhead 11 comprises (for example) four liquid discharge head 11y, 11c, 11m and 11k, wherein each liquid discharge head discharge respectively Huang (Y), blue or green (C), pinkish red (M), with the ink droplet of black (B) every kind of color, printhead 11 is installed on the carriage 4.The nozzle sequence that wherein is the nozzle surface 11a of the printhead 11 a plurality of ink-jet openings of formation (nozzle) is arranged along the direction of the sub scanning direction (band direction of transfer) vertical with main scanning direction.Inkjet direction is the downward direction of printhead 11 among Fig. 1.

Though use the liquid discharge head with standalone configuration in this embodiment, it can be configured to following structure: one or more printhead that wherein uses a plurality of nozzle sequences with the record drop of discharging every kind of color.

In this embodiment, printhead 11 is by a 11c, 11m, the 11y of four separation of the little ink droplet of discharging every kind of color, constitute with 11k, and each 11k, 11c, 11m, all is equipped with two row nozzle sequences with 11y, wherein is equipped with a plurality of nozzles side by side.

This head has one or more nozzle sequence, it arranges two row nozzle sequences, each nozzle sequence is discharged the black agent of every kind of color to this printhead 11, and also can be configured to discharge the black ink agent, it also can be by constituting with following, and it has one or more nozzle sequence of discharging every kind of color of color ink agent.

In the ink gun that constitutes printhead 11, be equipped with energy generation unit with the energy that generates ink-jet.This energy generation unit can be piezo-activator (for example piezoelectric element), or uses by utilizing electrothermal conversioning element (for example heat release resistor) to make the liquid film boiling with the thermal actuator by the phase transformation of variations in temperature.

But preferably, the energy generation unit of present embodiment uses piezo-activator.Under the situation of utilizing the heat release resistor with the hot type pressure generation unit of generation bubble, be difficult to good accuracy control point size, and must represent grey level to count out.On the other hand, under the situation of using piezo-activator, accuracy that can be good is controlled the displacement of piezoelectric element, and can change the size of formed point greatly, and the some size can be expressed many grey levels.In this case, in order to change diameter (perhaps forming many-valued point) a little, change the size of the voltage of driving pulse, i.e. the pulsewidth of driving pulse or pulse number or the like.But the present invention can be used for following situation, and is wherein only to form the point of single size, as described below.

In printhead 11, be equipped with drive IC (integrated circuit), and this drive IC is connected with the control module (not shown) by lead (flexible print cable or FPC cable) 12.

In carriage 4, be equipped with the son jars 15 of respective color, be used for providing the black agent of respective color to printhead 11.By the ink supply pipe 16 of respective color, from the print cartridge 10 of the respective color that attaches to print cartridge loading part 9 to the replenish the supply black agent of respective color of son jars 15.In this print cartridge loading part 9, form transfer pump unit 17, be used for carrying the black agent in each print cartridge 10.Ink supply pipe 16 is fixed to backboard IC (it constitutes framework 1) therebetween by locking member 18.

On the other hand, as being used for carrying the paper that is placed on paper feed tray 20 to be written into the paper feed unit 41 of the paper 22 on the parts (pressing plate) 21, be equipped with semicircle giving to send roller 23 and separating pad 24.Give and send roller 23 and separating pad 24 to face mutually, and be written into each that parts 21 separate conveyance of sheets 22 from paper.Separating pad 24 is made by the big material of coefficient of friction, and these separating pad 24 elasticity are pulled to sending roller 23 1 sides.

In order to send the downside conveyance of sheets 22 of unit from giving, the supporting element 28 that is equipped with induction element 25, reverse rollers 26, transmission induction element 27 and has forward position backer roll 29 to printhead 11.And conveyer belt 31 is for being used for when with electrostatic attraction paper 22, uploading paper feeding in the position relative with printhead 11 and open 22 delivery unit.

Conveyer belt 31 is an endless band, and it is wrapped between transfer roller 32 and the jockey pulley 33, thereby conveyer belt 31 is gone up at band direction of transfer (sub-scanning direction) around its circumference and moved.When moving conveyor belt 31, it charges with charging roller 34, thereby paper 22 is carried out electrostatic attraction.

Conveyer belt 31 can be made of single layer structure band or sandwich construction band.Under the situation of the conveyer belt 31 of single layer structure, the whole layer with 31 is all formed by insulating materials, and this is because be with 31 contact paper 22 and charging rollers 34.Under the situation of the conveyer belt 31 of sandwich construction, preferably, the side with paper 22 contacts with charging roller 34 with 31 is formed by insulating materials, and is formed by conductive material with a side that does not contact with paper 22 or charging roller 34 of 31.

Preferably, the insulating materials of the insulating barrier of the insulating materials of formation single layer structure conveyer belt 31 or formation sandwich construction conveyer belt 31 does not comprise conduction control material.The example of insulating materials can comprise resin or artificial rubber, for example PET, PEI, PVDF, PC, ETFE, PTFE.Specific insulation is preferably 1015 ohm-cms greater than 1012 ohm-cms.

Preferably, resin or artificial rubber conductive material that utilization can carbon containing form the conductive layer of sandwich construction conveyer belt 31.Specific insulation is in 105-107 ohm-cm scope.

Be equipped with charging roller 34 and form the insulating barrier (under the situation of sandwich construction band) on the surface of conveyer belt 31 with contact, and arrange charging roller 34 to make it can be according to the rotation servo-actuated and the rotation of conveyer belt 31.Pressurize to charging roller 34 in two ends at it.

Charging roller 34 is formed by conductive material, and its specific insulation is in 106-109 ohm-cm scope.With 2kV just/the AC bias voltage (high pressure) of negative polarity is applied to charging roller 34 from the AC bias voltage feeding unit (high voltage source) of later description.Though this AC bias voltage can use sinusoidal waveform and triangular waveform, this AC bias voltage preferably uses square wave.

At the back side of conveyer belt 31, induction element 35 is placed the position of the print range of corresponding printhead 11.Place induction element 35 with from the tangent line between two rollers (transfer roller 32 and jockey pulley 33) to printhead 11 projections, its upper surface support conveyor belt 31 is with the accurate flatness of the height of keeping conveyer belt 31.

When rotating transfer rollers 32 by rotating band 37 with timing roller 38, on the band direction of transfer of Fig. 2, carry out the circular motion of conveyer belt 31 by subscan motor 36.Though do not show, the encoder wheel that will wherein form slit is attached on the axle of transfer roller 32, is equipped with the transmission-type photoelectric sensor of the slit that detects encoder wheel.Encoder wheel and photoelectric sensor constitute wheeled encoder.

In addition, be equipped with and be used for separating disengaging pawl 41, the conveying roller 42 and conveying roller 43 of paper 22,, be used for and wherein be transported to discharge tray 40 by the paper 22 of printhead 11 document images as paper feeder unit from conveyer belt 31.

At the back side of framework 1, removably attached double-sided copying unit 51.The paper 22 that is returned by conveyer belt 31 reverse rotation is in the opposite direction caught in double-sided copying unit 51, and paper 22 is reverse, and paper 22 is delivered to the position between reverse rollers 26 and the conveyer belt 31 once more.Upper surface in double-sided copying unit 51 is equipped with manual bypass pallet 52.

The scanning direction of carriage 4 one of in the nonprinting region on the direction, place and safeguard Restoration Mechanism 61, be used for safeguarding and recovering the state of each nozzle of printhead 11.In safeguarding Restoration Mechanism 61, be equipped with: block element (or block) 62a-62d (it is referred to as " block 62 " when distinguishing not adding) is used for covering each nozzle surface 11a of printhead 11; Scraping blade 63, it is to be used for the blade element of wiping nozzle surface 11a; And sky tells acceptor 64, and it receives the black agent of not having contribution to printing, and when carrying out discharging this type of black agent when sky is told, with the record drop of discharge thickening.Be equipped with block 62a, drawing black agent and moistening nozzle surface, and be equipped with other block 62b-62d, be used for moistening nozzle surface.

In the nonprinting region on the opposite side of the carriage relative 4, be equipped with sky and tell acceptor 68 with main scanning direction.When carrying out sky when telling, sky is told acceptor 68 and is received liquid is discharged the black agent of not having contribution, to discharge the record liquid of thickening when printing.Sky is told acceptor 68 and is equipped with opening 69 along the nozzle rows direction of printhead 11.

As shown in Figure 1, in carriage 4, be equipped with the optical density (OD) sensor of making by infrared ray sensor (sensor type is not limited to this infrared ray sensor) 71 (it is used for detecting the existence of paper 22 for the recording medium detecting unit).Optical density (OD) sensor 71 places the upstream position of printhead 11 on the paper conveyance direction, and when carriage 4 playback, it is positioned at imaging scope (perhaps conveyer belt 31 1 sides).

Front side at carriage 4 is equipped with the encoder dish (encloderscale) 72 that wherein forms slit along main scanning direction.Be equipped with encoder detector 73 slit that detects encoder dish 72, that form by the transmission-type photoelectric sensor in the front side of carriage 4.Encoder dish 72 constitutes linear encoder 74 with encoder detector 73, and it detects the position of main scanning direction bracket 4.

The example of the liquid discharge head that forms the printhead in the ink jet printing device then, is described with reference to Fig. 3 and Fig. 4.

Fig. 3 is the profile along the liquid discharge head of the liquid chamber longitudinal direction of liquid discharge head.Fig. 4 is the profile of the liquid discharge head of the liquid chamber horizontal direction (nozzle array direction) along liquid discharge head.

Liquid discharge head comprises: channel plate 101, and it forms by monocrystal silicon substrate is carried out anisotropic etching; Vibrating reed (diaphragm) 102, its electroformed nickel by the lower surface that joins channel plate 101 to forms; And nozzle plate 102, it joins the upper surface of channel plate 101 to.These elements are combined together, and by lamination (laminate).

Thus, form nozzle communication path 105, liquid chamber 106, public liquid chamber 108 and ink supply port one 09.The nozzle 104 of discharging black agent (ink droplet) is communicated with liquid chamber 106 and public liquid chamber 108.Be equipped with public liquid chamber 108 and be used for, and ink supply port one 09 is communicated with public liquid chamber 108 to nozzle communication path 105 and liquid chamber 106 ink supply.

Be equipped with two row laminated-type piezoelectric elements 121, as the motor transducer, it be pressure generation unit (actuating unit), is used for deflection vibrating reed 102, and the black agent in the liquid chamber 106 is pressurizeed.Be equipped with base substrate 122, piezoelectric element 121 is fixed to base substrate 122 by engaging.Between piezoelectric element 121, form support unit 123.By the piezoelectric element material is carried out dividing processing, piezoelectric element 121 forms simultaneously with support unit 123.Support unit 123 does not receive driving voltage, and they are support component.

The FPC cable 122 that drive circuit (drive IC does not show) will wherein be installed is connected to piezoelectric element 121.

Frame element 130 combines with vibrating reed 102 peripheries.In frame element 130, form recessed portion, thereby use this recess to assign to form insertion portion 131 and public liquid chamber 108.Comprise that the piezoelectric element 121 and the actuating unit of base substrate 122 are inserted in the insertion portion 131.In addition, in frame element 130, form ink supply aperture 132, ink supply aperture 132 is used for from the outside to public liquid chamber 108 ink supply.For example, injection-molded by hot setting glue (for example epoxy resin or polyphenyl sulfenyl resin) forms frame element 130.

In the present example, by the monocrystal silicon substrate with crystal plane orientation (110) being carried out anisotropic etching, form channel plate 101 with alkaline etching solution (for example potassium hydroxide (KOH) solution).Thus, form recessed portion and the bore portion that is used as nozzle communication path 105 and liquid chamber 106.But, the invention is not restricted to monocrystal silicon substrate.Replacedly, can alternatively use the stainless steel-based end, photosensitive resin or the like.

In the present example, vibrating reed 102 is formed by the nickel metallic plate, and is prepared by electrocasting method.Replacedly, can alternatively use the composition element of another metallic plate or metallic plate and resin plate.

Piezoelectric element 121 joins vibrating reed 102 with support unit 123 to by adhesive agent, and frame element 130 further joins vibrating reed 102 to by adhesive agent.

In nozzle plate 103, form nozzle 104, each nozzle diameter is all in the 10-30 micrometer range and corresponding to each liquid chamber 106.Nozzle plate 103 joins channel plate 101 to by adhesive agent.Thereby be equipped with nozzle plate 103 and on the surface of nozzle formation element (it is made by hardware), form given layer, and on the top on this surface of given layer, form watertight composition.The surface of nozzle plate 103 forms said nozzle surface 34a.

Piezoelectric element 121 is laminated-type piezoelectric element (PZT), wherein alternately lamination piezoelectric 151 and internal electrode 152.Each electrode 153 is connected to each internal electrode 152 with public electrode 154, these internal electrodes 152 is pulled out to the corresponding end-faces of piezoelectric element 121.

In the present example, piezoelectric element 121 has following structure, wherein utilizes as the displacement on the d33 direction of the piezoelectricity direction of piezoelectric element 121, to the black agent pressurization in the liquid chamber 106.Replacedly, can use following structure, wherein utilize, to the black agent pressurization in the liquid chamber 106 as the displacement on the d31 direction of the piezoelectricity direction of piezoelectric element 121.

In addition, can use following structure, wherein in single substrate 122, be equipped with delegation's piezoelectric element 121.

In above-mentioned liquid discharge head, the voltage that is applied to piezoelectric element 121 is reduced to is lower than reference potential, piezoelectric element 121 shrinks, and vibrating reed 102 descends, thus the volume of liquid chamber 106 enlarges, and black agent flow in the liquid chamber 106.Increase the voltage that is applied to piezoelectric element 121, piezoelectric element 121 extends on laminating direction.Vibrating reed 102 is at the direction upper deflecting of nozzle 104, and the volume of liquid chamber 106 dwindles, thereby the black agent in the liquid chamber 106 is pressurized, and discharges ink droplets (record liquid) from nozzle 104.

By making the voltage that is applied to piezoelectric element 121 turn back to reference potential, vibrating reed 102 turns back to initial position, and liquid chamber 106 expansions, thereby negative pressure occurs in liquid chamber 106.At this moment, in liquid chamber 106, charge into record liquid from public liquid chamber 108.

Then, the vibration on the falcate surface of nozzle 104 reduces and settles out, and the work of liquid discharge head is transferred to the discharge work of ink droplet subsequently.

The driving method of liquid discharge head is not limited to above-mentioned example.Can alternatively use another driving method (pushing away the formula of beating).

In above-mentioned ink jet printing device, carry out the separation from a piece of paper of the paper 22 of paper feed unit is sent into, and the paper of upwards sending into 22 is by induction element 25 guiding.Between conveyer belt 31 and reverse rollers 26, insert paper 22, and transmit paper 22.The forward position of paper 22 guides by transmitting induction element 27, and pushes paper 22 by forward position backer roll 29 to conveyer belt 31, thereby paper 22 is transmitted on paper conveyance direction with about 90 degree.

At this moment, alternately provide the voltage of positive potential and the voltage of negative potential from AC bias voltage feeding unit to charging roller 34.That is, provide the voltage that alternately changes to conveyer belt 31 by charging roller 34.The banded alternation zone that in conveyer belt 31, has the positive and negative charging of charging voltage pattern of pressing preset width.

When transporting paper 22 on the conveyer belt 31 with the positive-negative polarity charging alternately, paper 22 is drawn up by electrostatic force by conveyer belt 31, and the circular motion by conveyer belt 31, transmission paper 22 on sub scanning direction.

Then, in movable support bracket 4, drive printhead 11, and discharge ink droplet, thereby on paper 22, form the delegation of image to the paper 22 that is stopped according to picture signal.After paper 22 is transmitted given conveying capacity, on paper 22, form the next line of image.

When receiving printing finished signal, perhaps when receiving that indication paper 22 ends have reached the detection signal of imaging scope, stop printing.Then paper 22 is delivered to discharge tray 40.

Under the situation of duplex printing, when the printing of the front surface of finishing paper 22, reverse rotation conveyer belt 31 is sent the paper 22 of wherein imaging on front surface into duplex printing unit 51.Reverse paper 22 (carrying on the back under the state that surface modification is a print surface), and paper 22 delivered to position between reverse rollers 26 and the conveyer belt 31 once more.

After having carried out the transmission of paper 22 by timing controlled conveyer belt 31, imaging on the back side of paper 22.Then, paper 22 is delivered to discharge tray 40.

When utilizing above-mentioned ink jet printing device on paper, to print wherein to embed indication to forbid the image of shading of copied files, there is following problem, promptly be attached to the fiber pervasion of the ink droplet of paper along paper, this problem is that inkjet printing is distinctive.Alleviate the diffusion of ink droplet and the black agent of emergence as far as possible in order to realize the shading printing, preferably to use.

The black agent that preparation is used by above-mentioned ink jet printing device is to comprise following component (1) to (10).Use pigment as the colouring agent that is used to print, and be used for decomposing solvent with dispersed color as basis.In addition, also use wetting agent, surfactant, emulsifying agent, anticorrisive agent and pH conditioning agent as additive.The purpose of mixing wetting agent 1 and wetting agent 2 is to make viscosity to control easily, and controls the characteristic of wetting agent respectively.

(1) pigment (from pigment dispersion) 6wt% or more

(2) wetting agent 1

(3) wetting agent 2

(4) water-miscible organic solvent

(5) anion or non-ionic surface active agent

(6) carbon number 8 or higher polyol or ethylene glycol

(7) emulsifying agent

(8) anticorrisive agent

(9) pH conditioning agent

(10) pure water

The black agent of being used by above-mentioned ink jet printing device comprises said components (1) to (10).When using above-mentioned black agent on plain paper during print image, can obtain high image density, can not cause the clear quality and the good color tone (sufficient painted characteristic and color reproduction characteristic) of image of the emergence phenomenon of character and image.Thus, when the printing of the image that wherein embeds shading, can clearly reproduce the point (background parts and the mark part that indicates that it is copy) of shading.Can prevent that mark part from fogging, perhaps can prevent because the natural beige in the background parts that causes according to the difference of the reproducibility of a size pollutes (natural complexion soil).

The structure of the control module of this ink jet printing device then, is described with reference to Fig. 5.

As shown in Figure 5, control module 200 comprises: CPU 201, and its management is to the control of whole ink jet printing device; ROM 202, program and other fixed datas that its storage is carried out by CPU 201; RAM203, its temporary transient storing image data or the like; Rewritable non-volatile memory 204 is even it still preserves the data that will write when closing the power supply of this equipment; And ASIC 205, it carries out various signals to view data handles, to the processing that rearranges of view data, and to the processing of input/output signal with the control entire equipment.

In addition, control module 200 also comprises: HPI (I/F) 206, a driving control unit 207, head driver (drive IC) 208, main scan motor driver element 210, subscan motor drive unit 211, AC bias voltage feeding unit 212, and I/O interface 213.Be equipped with main frame I/F 206 to send or to receive whereabouts/from the data and the signal of host computer system.Driving control unit 207 comprises and is equipped with the data transfer unit that printhead 11 is driven control.Printhead 11 is provided in carriage 4 one sides with head driver 208.Head driver 208 is for being equipped with a driving arrangement that drives printhead 11.

Main scan motor driver element 210 is equipped with drives main scan motor 5.Subscan motor drive unit 211 is equipped with drives subscan motor 36.AC bias voltage feeding unit 212 is equipped with to provide AC bias voltage to charging roller 34.I/O interface 213 is equipped with the detection pulse imported from linear encoder 74 and wheeled encoder 236, from the detection signal of the temperature sensor 215 of testing environment temperature and from the detection signal of other various sensors.

Guidance panel 214 also is connected to control module 200, and this guidance panel 214 is equipped with and imports and show the operation information that ink jet printing device is required.

Control module 200 utilizes main frame I/F 206, receive from print data host computer system, that comprise view data by cable or network, this host computer system comprises the imaging device of digital camera for example, such as the cis of imageing sensor etc. and such as the data processing equipment of personal computer etc.

The CPU 201 of control module 200 reads and analysis package is contained in print data in the reception buffer among the main frame I/F 206, make 205 pairs of print datas of ASIC carry out required image and handle and rearrange processing, and send the view data of a driving control unit 207 certainly to head driver 208.Can create the dot pattern data that is used for carrying out image output by in ROM 202, storing font data.Printer driver that perhaps can be by utilizing host computer system one side, view data is developed into data bitmap and data bitmap is sent to control module 200, create the dot pattern data that being used for carrying out image output.

Driving control unit 207 sends above-mentioned view data as serial data to head driver 208, and the output tranmitting data register and latch signal and the control signal that are used for sending view data and are used for determining sending.In addition, a driving control unit 207 comprises the drive waveforms creating unit, and it comprises D-A converter and amplifier or the like, and it carries out the D/A conversion to storage in ROM 202 and by CPU 201 pattern datas that read, driving pulse.The drive waveforms creating unit of driving control unit 207 is created the drive waveforms that is made of one or more driving pulse (driving signal), and to head driver 208 output drive waveforms.

Head driver 208 comprises: shift register, its receive clock signal and serial signal (it is the view data from a driving control unit 207); Latch cicuit, it is by the latch signal from a driving control unit 207, the register value of latch shift register; Level shifting circuit (level translation device), its output valve to latch cicuit is carried out level conversion; And analog switch array (switch element), its on/off state is controlled by level shifting circuit.The on/off state of head driver 208 control analog switch array, and optionally be provided at the driving pulse that comprises in the drive waveforms from a driving control unit 207 to the actuating unit (piezoelectric element 121) of printhead 11, thus drive printhead 11.

Main scan motor driver element 210 calculates controlling value according to the speed detected value that obtains from the detection pulse of linear encoder 74 by sampling and from the desired value of CPU 201 1 sides, and by internal motor driver drives main scan motor 5.

Similarly, subscan motor driving control unit 211 is according to the speed detected value that obtains from the detection pulse of wheeled encoder 236 by sampling and from the desired value of CPU 201 1 sides, calculate controlling value, and by internal motor driver drives subscan motor 36.

The example of structure of a driving control unit 207 and head driver 208 is then described with reference to Fig. 6.

Driving control unit 207 is equipped with lower unit 301 and 302.Drive waveforms generation unit 301 generates and exports the drive waveforms (common driver waveform) that comprises a plurality of driving pulses (driving signal) in a tap-off cycle.Data transfer unit 302 output image datas (print data), tranmitting data register, latch signal and ink droplet control signal.Ink droplet control signal M0-M3 is used for commanding the disconnection/closed condition for analog switch 315 each ink droplet, head driver 208.According to the tap-off cycle of common driver waveform, by selecteed waveform the state of each ink droplet control signal is changed into the H level, and when non-selected, the state of each ink droplet control signal is changed into the L level.

Head driver 208 is equipped with lower unit 311 to 315.Shift register 311 inputs are from the tranmitting data register (shift clock) and the serial image data of data transfer unit 302.Latch cicuit 312 is by each register value of latch signal latch shift register 311.Decoder 313 decode image data and ink droplet control signal M0-M3, and output result signal.According to the output of the decoder 313 that receives by level translation device 314, on-off (opening or closing) analog switch 315.Level translation device 314 is the level that analog switch 315 can be worked with the level conversion of the logic-level voltages signal of decoder 313.

Analog switch 315 is connected to the selection electrode (each electrode) 154 of each piezoelectric element 121, and imports the common driver waveforms to analog switch 315 from drive waveforms generation unit 310.Therefore, according to the output data and the control signal of decoder 313 of the view data of decoding serial transfer, conducting analog switch 316 transmits necessity driving signal that (selections) constitutes the common driver waveform, thereby it is applied to piezoelectric element 121.

The operation of head driver 208 is then described with reference to Fig. 7.

Shown in Fig. 7 (a), 301 outputs of drive waveforms generation unit comprise the common driver waveform of a plurality of pulses (driving signal) P1, P2, P3.In an ink droplet tap-off cycle, this waveform descends from reference potential V1 (middle electromotive force) (along the direction of expansion liquid chamber volume), and after the process predetermined hold-time, this waveform rises to reference potential V1 (along the direction of dwindling the liquid chamber volume).

By discharging two ink droplets and during flying, make up them, form a big ink droplet by pulse signal P1 and pulse signal P2.Because the decline electromotive force of the ripple element of pulse signal P2 is lower than the electromotive force of pulse signal P1, thus pulse signal P2 only form in ink droplet.Make the electromotive force of decline of the ripple element of pulse signal P3 be lower than the electromotive force of pulse signal P2, and this waveform is risen gradually, and only form little ink droplet by pulse signal P3.

When selecting big ink droplet, the big ink droplet control signal M0 of drive waveforms generation unit 301 outputs, wherein fractional t1 and the T2 corresponding to pulse P1 and P2 is set to the H level, shown in Fig. 7 (b) and 7 (c).When selecting China and Mexico to drip, ink droplet control signal M1 in 301 outputs of drive waveforms generation unit, wherein the part T2 corresponding to pulse P2 is set to the H level, shown in Fig. 7 (d) and 7 (e).When selecting little ink droplet, the little ink droplet control signal M2 of drive waveforms generation unit 301 outputs, wherein part T3 is set to the H level, shown in Fig. 7 (f) and 7 (g).When not selecting discharge point, keep voltage V1, shown in Fig. 7 (h).

Therefore, according to the view data of sending, can select big ink droplet, middle ink droplet, little ink droplet and do not discharge from data transfer unit 302.Therefore, can form four grey levels of image according to many-valued point with the size that comprise a little bigger, mid point, point and not discharge.

In this ink jet printing device, store the execution of the present invention program that is used for exporting the process of the formation method that comprises the print image of indicating the shading of forbidding copied files of the present invention.

Fig. 8 is for showing the block diagram comprise as the structure of the print system of the ink-jet printer of the ink jet printing device of the invention described above and image processing equipment.

Predetermined interface of passing through or predetermined network are connected to one or more image processing equipment 400 and the ink-jet printer 500 of personal computer (PC), thereby constitute print system (imaging system).

When display image treatment facility 400 in Fig. 9, connect CPU401 and as the various ROM 402 and RAM 403 of memory cell by bus.Utilize the memory 406 (for example hard disk) of magnetic storage apparatus to be connected to this bus by predetermined interface.Be connected with input equipment 404 (for example mouse or keyboard) and display device 404 (for example LCD and CRT (though show)), connect and read such as the predetermined interface memory medium reader of storage mediums such as CD and that communicate by letter with the external device (ED) network and the USB of internet (for example as) (exterior I/F) 407.

Storage comprises the image processing program of program of the present invention in the memory 406 of image processing equipment 400.Utilize memory medium reader in storage medium, to read this image processing program, perhaps download this image processing program, and in memory 406, this image processing program is installed from network (as the internet).

By this installation, will be in following state: this image processing program can move, thereby image processing equipment 400 can be carried out with hypograph and handles.

This image processing program can move on predetermined OS.The specific part of this image processing program can be made as application program.

Explain the example of the program of image processing equipment 400 1 sides of carrying out image processing method of the present invention with reference to the functional-block diagram of Figure 10.

This is following situation: nearly all image is handled all and is carried out by the master computer (as PC) as image processing equipment, and is the structure of the ink jet printing device of the equipment that is suitable for being used for relatively low cost.

Printer driver 411 as the program related to the present invention of image processing equipment 400 (PC) side comprises: CMM (color management module) processing unit 412, the view data 410 that will provide from application software etc. from the color notation conversion space that is used for monitor and shows to the color space that is used for tape deck (RGB color coordinates-CMY color system); BG/UCR/ γ correcting unit 413, carry out from the value of CMY, carrying out black generate/BG/UCR (black generates/low colour removal) of low colour removal handles and reflected that the γ that the input and output of the characteristic of record equipment or user's hobby are proofreaied and correct proofreaies and correct; Unit for scaling 414 consistently with the resolution ratio of record equipment amplifies processing; Halftone process unit (many-valued/few value matrix) 415 comprises the many-valued/few value matrix that view data is replaced as the arranged in patterns of the point that sprays from the record equipment; Gridding unit 416, the dot pattern data as print image data that file/burelage synthesis unit 418 of discussing is from behind obtained is divided into each each data that scan, and then the consistent data of carrying out with each nozzle location that writes down develop; Printed driver 411 outputs to ink-jet printer 500 with the output 417 of gridding unit 416.

And then, this printer driver 411 has file/burelage synthesis unit 418, described file/burelage synthesis unit 418 will be from the halftone process unit document images of 415 outputs and expression be that the data of the picture pattern (to call ' burelage ' in the following text) of the file that duplicated by forbidding of being generated of burelage generation unit 419 superpose synthetic, wherein, 415 pairs of described halftone process unit carry out image with the original images (to call ' document image ' in the following text) of above-mentioned view data 410 expressions to be handled, and is transformed into and the many-valued corresponding data that can be exported by ink jet printing device 500.Utilize this document/burelage synthesis unit 418 will with can synthesize by the many-valued some corresponding file view data of ink-jet printer 500 output and the data of burelage, thus, generate and the many-valued corresponding print image data that can export by ink-jet printer 500.

Then, with reference to the functional-block diagram explanation of Figure 11: mainly carry out image processing method related to the present invention, and image processing equipment 400 sides are shared a part of example of execution in ink-jet printer 500 sides.Handle because can carry out image at a high speed, so the structure of Figure 11 can be used rightly at high-speed equipment.

The printer driver 421 of image processing equipment 400 (PC) side has: CMM (color management module) processing unit 423, the view data 410 that will provide from application software etc. from the color notation conversion space that is used for monitor and shows to the color space that is used to write down equipment (RGB color coordinates-CMY color system); BG/UCR/ γ correcting unit 424, carry out from the value of CMY, carrying out black generate/BG/UCR (black generates/low colour removal) of low colour removal handles and reflected that the γ that the input and output of the characteristic of record equipment or user's hobby are proofreaied and correct proofreaies and correct; Printer driver 421 will send to ink-jet printer 500 by the view data as file that this BG/UCR/ γ correcting unit 424 generates.

On the other hand, the printer controller 511 of ink-jet printer 500 (control module 200) comprises: unit for scaling 514, consistently with the resolution ratio of record equipment amplify processing; Halftone process unit (many-valued/few value matrix) 515 comprises the many-valued/few value matrix that view data is transformed into the pattern arrangement of the point that sprays from the record equipment; Gridding unit 516 dot pattern data of file/print image data that burelage synthesis unit 518 obtains of discussing from behind is divided into the data of each each scanning, and then the consistent data of carrying out with each nozzle location that writes down develops; Printer controller 511 offers a control module 207 with the output of gridding unit 516.

And then, this printer controller 511 has file/burelage synthesis unit 518, described file/burelage synthesis unit 518 will be from the halftone process unit document images of 515 outputs and expression be that the data of the picture pattern of the file that duplicated by forbidding of being generated of burelage generation unit 519 superpose synthetic, wherein, 515 pairs of described halftone process unit carry out image with the represented document image of view data from image processing equipment 400 inputs to be handled, and is transformed into and the many-valued corresponding data that can export.Utilize this document/burelage synthesis unit 518 to synthesize, thus, generate and the many-valued corresponding print image data that can export with the data of many-valued some corresponding file view data can exporting and burelage.

Even the structure of Figure 10 and Figure 11 also can suitably be used the image processing method among the present invention.Here, structure as shown in figure 10 has been described,, has not had in the equipment and produce describing or the print command of literal and produce the function of the dot pattern that writes down practically of acceptance pattern picture in the ink jet printing device side.Promptly, print command from application software performed in the image processing equipment 400 as main frame etc. is illustrated with following example: carry out image and handle by be installed in printer driver 411 in the image processing equipment 400 (master computer) as software, thereby the data (print image data) of the many-valued dot pattern that generation ink-jet printer 500 can be exported, these data by gridding after, be sent to ink-jet printer 500, ink-jet printer 500 prints output.The example of the ink-jet printer 500 that description is printed.

Particularly, in image processing equipment 400 (master computer), use application program (for example Word of Microsoft or Excel (registration mark)), draw such as file datas such as tabulation and files.

For from application in the master computer or operating system, printer driver 411, at the print command of this document image (as mentioned above, in order to utilize ink-jet printer 500 to print), carrying out image handles, for example CMM, BG, UCR, convergent-divergent, γ conversion and many-valued and few value matrix are handled, and create the drawing data of document image, it comprises the some size information that can utilize ink-jet printer 500 to reproduce.

On the other hand, create burelage by burelage creating unit 419.In burelage creating unit 419, generate the burelage (picture pattern) that comprises the some size information that to utilize ink-jet printer 500 reproductions.That is, for the data of burelage and be identical for the value of some size information drawing data, ink-jet printer 500 that derives from file.

For example, suppose by 2 bits (bit 1, bit 0) data representation four the value points.If the data of (bit 1, bit 0) are (00), then its indication is not printed.If the data of (bit 1, bit 0) are (01), then it indicates droplet.If the data of (bit 1, bit 0) are (10), then drip in its indication.If the data of (bit 1, bit 0) are (11), then its indication is big drips.

Then, will processing that be created the burelage data by burelage creating unit 419 be described.

In image processing equipment 400, in memory 406 (for example predetermined memory), preserve the data of burelage.CPU 401 reads the data of this burelage from memory 406.Adjust the size of burelage data, thereby it can draw and the data that generate according to the many-valued point that can export of the ink-jet printer 500 of the burelage of whole paper surface size on the whole file size of printed material.

And by the file of printer driver 411 and the data and the document image (file) of burelage synthesis unit 418 synthetic burelage.

Document image is multi-value data (for example 2 bits), and for example, combined treatment is identical with the burelage data to multi-value data.For the data that wherein indication is not printed in document image, the data of (bit 1, bit 0) are (00).

Therefore, have only when document image is (00), just the burelage data are carried out OR and handle (, after combination, being set to " 1 ") if a bit is " 1 ".When the burelage data were many-valued point data in the non-printing portion of document image, non-printing portion was changed into many-valued view data (print data).

Then, according to ink-jet printer 500 the head structure, print the gridding of view data by gridding unit 216, and have according to each direction of nozzle or the print image data of the delay that the data transaction of arranging provides, it is sent to ink-jet printer 500 by interface.

Ink-jet printer 500 is stored the print image data that sends in the grid data storage.After ink-jet printer 500 was received tentation data, it printed the image of include file image and burelage by driving printhead 11 according to print image data on paper 22.

Then, describe shading of the present invention with reference to Figure 12 to Figure 18 and print (unauthorised copies prevention/information leakage stops system).

Figure 12 and Figure 13 are used for explaining the diagram that burelage is printed.Figure 14 and Figure 15 are used for explaining the diagram that generates the effect of shading in prospect part and background parts.Figure 16 and Figure 17 are the diagram that is used for explaining according to the shading reproducibility of droplet size.Figure 18 is the diagram that is used for explaining the shading generation method of the point that utilizes tiny some set.

More than explained the flow process that shading is printed.Shown in Figure 12 (a), ink-jet printer 500 obtains printed material (original image), wherein embeds character or pattern as shading, and if the copy printed material, shown in Figure 12 (b), shading then appears.In this example, character 600 (" copy ") embeds the prospect part of Figure 12 (a) printed material (original image).

Whether can distinguish thus, is the copy that reproduces from the printed material of being concerned about.By using the shading that can discern, this helps to stop illegal copies.

This shading is printed the background removal function of using duplicator.That is, under the situation of background removal function, tinyly after copy, can not occur, but have only the size just can appearance after copy greater than the point of certain threshold.Shown in Figure 13 (a), when printed material by a little bigger 601 with point 602 when forming, after copy, reproduce a little louder 601, still can not reproduce point 602, shown in Figure 13 (b).

In formation method of the present invention, shown in Figure 14 (a), in the prospect part of original image, be included in the point 601 (black character " A ") that copy reproduces afterwards, and in the background parts of original image, be included in the point 602 that can not reproduce after the copy.That is, in character " A " (shading) the embedding prospect part.

If copy this printed material, shown in Figure 14 (b), then have only the image of prospect part reproduced, and character " A " in copy, occurs.

In this example, the character " A " (shading) in the prospect part of embedding original image can appear in the copy.In other words, make the record liquid bond area of the record liquid bond area of each point on the unit are in the prospect part, thereby the character " A " in the prospect part in copy, can occur greater than each point on the unit are in the background parts.

On the contrary, shown in Figure 15 (a), in the background parts of original image, be included in the point 601 that reproduces after the copy, and in the prospect part of original image, be included in the point 602 that can not reproduce after the copy.That is, white characters " A " (shading) embeds in the background parts.

If copy this printed material, shown in Figure 15 (b), then have only the image of background parts reproduced, and white characters " A " (shading) in copy, occurs.In other words, make the record liquid bond area of the record liquid bond area of each point on the unit are in the background parts, thereby the white characters " A " in the background parts in copy, occurs greater than each point on the unit are in the prospect part.

In above-mentioned shading was printed, shading was made of the set with background parts of the prospect part of original image, and does not make the image of prospect part showy before copy.Replacedly, can be configured and make shading only partly constitute by prospect.

Be provided as at ink jet printing device under the situation of point of variable-size, in prospect part and one of background parts, embed the image of indicating the shading of forbidding copying original image, and in prospect part and one of background parts, comprise a little louder, in prospect part and background parts, comprise point in another.The difference of the record liquid bond area of each point makes it possible to form shading in the copy at printed material after copy on the unit are between prospect part and the background parts.

Then, with the formation method of describing under the situation of point that ink jet printing device is provided as fixed size of the present invention.

With reference to Figure 16 and Figure 17 reproducibility according to the shading of droplet size is described.

Figure 16 shows the reproducibility that can be had the shading under large-sized situation by the ink droplet that ink jet printing device is discharged.Figure 17 shows the reproducibility that can be had the shading under the undersized situation by the ink droplet that ink jet printing device is discharged.

Big and put when big when ink drop size, can reproduce this point.As shown in figure 16, can in the prospect part, comprise shading, but can not in background parts, comprise shading.

On the other hand, the shading that is made of point does not have reproducibility.Do not reproduce the image that foreground portion is divided.As shown in figure 17, can in background parts, comprise shading, but can not in the prospect part, comprise shading.

The shading generation method of the point that utilizes tiny spot size then, is described with reference to Figure 18.After copy, do not reproduce tiny point, and can not in the prospect part, comprise the shading that uses tiny point.But, can use the tiny point of a plurality of vicinities that constitutes shading to obtain and a little bigger the same big black agent bond area.Can utilize a plurality of contiguous points, obtain good shading reproducibility.

Even copy original image in this state, also can after copy, reproduce a little.For example, when arranging tiny point 611 by preset distance, shown in Figure 18 (a), after copy, do not reproduce them, shown in Figure 18 (b) with being spaced apart.

On the other hand, when contiguous tiny point 611 set be expert at by the concentrated area at interval according to preset distance with row in when being arranged as a set 612, shown in Figure 18 (a), after copy, reproduce them, shown in Figure 18 (b).

Particularly, shown in Figure 19 A and Figure 19 B, in the background parts of original image, comprise the 2x2 neighbor point set of counting and separating, and in the prospect part, comprise the 3x3 neighbor point set of counting and separating by given by given.Replacedly, can arrange the point of this moment to arrange, make in background parts, to comprise discretely a little, and only in the prospect part, comprise the neighbor point set.

Therefore, can carry out shading and print, make the prospect part constitute, and background parts be made of tiny point by contiguous tiny some set.

There is the low situation of resolution ratio, the spacing between the neighbor point big (even it is also like this to arrange neighbor point), and each point is separated from each other.In this case, will be discharged to same position on the recording medium corresponding to a plurality of ink droplets of a plurality of neighbor points.Generation is soaked into recording medium, and obtains enough black agent bond areas of each required point of background parts.Perhaps, reach the arrangement of a plurality of neighbor points by control the some drain position on the recording medium in electric mode.

In this case, operate the same position that a plurality of ink droplets can not be discharged on the recording medium by carrying out a main scanning, and, a plurality of ink droplets are discharged to same position by repeating repeatedly main scanning operation continuously.

Thus, form a plurality of neighbor points, be embedded in shading in prospect part and one of background parts with formation.Perhaps, form a plurality of neighbor points that constitute shading by a plurality of ink droplets being discharged to the same position on the recording medium.Even, also can obtain the reproducible record liquid bond area of each point, and can print shading when being equipped with ink jet printing device when forming the point of single fixed size.Also can carry out shading under the situation of low resolution prints.

Different with the imaging device of photoelectricity Method of printing, under the situation of ink jet printing device, after black agent is attached to recording medium, black agent may takes place soak into.Under the situation of ink jet printing device, can not in printing, the shading that the imaging device that is using the photoelectricity Method of printing uses distinguish prospect part and background parts by number of pixels, importantly consider the ink droplet bond area.

The diameter of the point that can be reproduced by ink jet printing device (duplicator) is according to the light characteristic of print colors and difference.Under the situation of high brightness (becoming clear), reproduce the situation of the diameter of required point after the copy greater than low-light level (darkness).For example, must make print colors is that the diameter of the point of the prospect part under the situation of cyan is the situation of black greater than print colors.Changing black agent bond area according to the light characteristic level enables to carry out the shading printing with various print colors.

As shown in figure 17, when in prospect part, forming when comprising the shading of tiny point 602, the thresholding of the duplicator of the black agent bond area that makes the shading that in original image, embeds during less than the copy original image.Therefore, can be formed in the shading that comprises in the original image, thereby shading does not occur in the image of reproduction of copy after it.Whether by utilizing this feature, can detect is copy image.

The invention is not restricted to the foregoing description, and under the prerequisite that does not depart from the scope of the present invention, can change and modification.

In addition, the present invention is based on Japanese patent application of submitting on March 18th, 2005 2005-078349 number and the Japanese patent application of submitting on July 21st, 2005 2005-210724 number, and require its priority, its content all incorporates this paper by reference.

Claims (20)

1. formation method is used for forming a little ink jet printing device by discharging the record drop on recording medium, and this formation method may further comprise the steps:

Form wherein the image that embeds shading in the prospect part of original image and one of background parts, this shading is indicated and is forbidden copying original image; And

Make the record liquid bond area of putting on the unit are in the prospect part be different from the record liquid bond area of putting on the unit are in the background parts,

Wherein, carrying out shading prints, make described prospect part constitute by first set of neighbor point, described background parts is made of second set of neighbor point, and when described prospect part obtained described foreground portion and divides the enough black agent bond area of each required point by the black agent of described recording medium is soaked into, described prospect part constituted by the 3rd set of first set of described neighbor point being changed into by the given neighbor point that separates of counting.

2. formation method as claimed in claim 1, wherein a plurality of neighbor points constitute shading.

3. formation method as claimed in claim 1 wherein by a plurality of record drops being discharged to the same position on the recording medium, forms a plurality of neighbor points that constitute shading.

4. formation method as claimed in claim 1 wherein according to the light characteristic of the color of the record liquid that uses, changes the record liquid bond area of putting on the unit are.

5. formation method as claimed in claim 1, the record liquid bond area of wherein putting on the unit are in the background parts is greater than the record liquid bond area of putting on the unit are in the prospect part.

6. formation method as claimed in claim 1, wherein the record liquid bond area of putting on the unit are in the prospect part is greater than the record liquid bond area of putting on the unit are in the background parts.

7. formation method as claimed in claim 1 wherein be equipped with the point of described ink jet printing device for formation variable-size on recording medium, and a plurality of neighbor point constitutes shading.

8. formation method as claimed in claim 7 wherein by a plurality of record drops being discharged to the same position on the recording medium, forms a plurality of neighbor points that constitute shading.

9. formation method as claimed in claim 7 wherein according to the light characteristic of the color of the record liquid that uses, changes the record liquid bond area of putting on the unit are.

10. formation method as claimed in claim 1 wherein be equipped with the point of described ink jet printing device for formation fixed size on recording medium, and a plurality of neighbor point constitutes shading.

11. formation method as claimed in claim 10 wherein by a plurality of record drops being discharged to the same position on the recording medium, forms a plurality of neighbor points that constitute shading.

12. formation method as claimed in claim 10 wherein according to the light characteristic of the color of the record liquid that uses, changes the record liquid bond area of putting on the unit are.

13. formation method as claimed in claim 10, the record liquid bond area of wherein putting on the unit are in the background parts is greater than the record liquid bond area of putting on the unit are in the prospect part.

14. formation method as claimed in claim 10, wherein the record liquid bond area of putting on the unit are in the prospect part is greater than the record liquid bond area of putting on the unit are in the background parts.

15. formation method as claimed in claim 1 wherein is equipped with the point of described ink jet printing device for formation fixed size on recording medium, and by a plurality of record drops being discharged to the same position on the recording medium, forms a plurality of neighbor points that constitute shading.

16. formation method as claimed in claim 15 wherein according to the light characteristic of the color of the record liquid that uses, changes the record liquid bond area of putting on the unit are.

17. formation method as claimed in claim 15, the record liquid bond area of wherein putting on the unit are in the background parts is greater than the record liquid bond area of putting on the unit are in the prospect part.

18. formation method as claimed in claim 15, wherein the record liquid bond area of putting on the unit are in the prospect part is greater than the record liquid bond area of putting on the unit are in the background parts.

19. formation method as claimed in claim 1, wherein,

When the resolution ratio of described ink jet printing device is hanged down, form a plurality of points that each point is separated from each other by the some drain position of controlling in electric mode on the recording medium.

20. an ink jet printing device, it forms on recording medium a little by discharging the record drop, and this ink jet printing device comprises:

The burelage creating unit is used for forming wherein the image that embeds shading in the prospect part of original image and one of background parts, and this shading is indicated and forbidden copying original image; And

Control module is used for making the record liquid bond area of putting on the unit are in the prospect part to be different from the record liquid bond area of putting on the unit are in the background parts,

Wherein, described ink jet printing device carries out shading and prints, make described prospect part constitute by first set of neighbor point, described background parts is made of second set of neighbor point, and when described prospect part obtained described foreground portion and divides the enough black agent bond area of each required point by the black agent of described recording medium is soaked into, described prospect part constituted by the 3rd set of first set of described neighbor point being changed into by the given neighbor point that separates of counting.

Images