CN100570504C - Image processing system - Google Patents

Abstract

The invention provides a kind of image processing system, comprising: as supporting body, this has photographic layer as supporting body, and the electrostatic capacitance of above-mentioned photographic layer per unit area is more than or equal to 1.7 * 10-6 (F/m2); And developing apparatus, look like to develop to being formed at above-mentioned static with developer as supporting body, on above-mentioned picture supporting body, form the toner picture, wherein, if the quantity of electric charge of the per unit weight of above-mentioned toner picture is Q/M (C/g), the potential difference (PD) of the surface potential of above-mentioned picture supporting body and the flip-flop of above-mentioned developing bias voltage is Vcont (V), the toner weight of the per unit area of the maximum concentration portion of above-mentioned toner picture is M/S (g/m2), the thickness of toner layer is Lt (m) in the maximum concentration portion of above-mentioned toner picture, the thickness of above-mentioned photographic layer is Ld (m), the relative dielectric constant of above-mentioned toner layer is ε t, the relative dielectric constant of above-mentioned photographic layer is ε d, the specific inductive capacity of vacuum is ε 0 (F/m), then satisfies following formula 1.| Q/M| 〉=0.95 * Vcont/ ((M/S) * (L _t/ 2 ε ₀ε _t+ Ld/ ε ₀ε _d)) ... (formula 1)

Description

Image processing system

Technical field

Thereby the present invention relates to be formed at as the static on the supporting body as image processing systems such as the visual duplicating machine that obtains image, printers with toner.Relate in particular to as the photographic layer as supporting body, the electrostatic capacitance of using per unit area is more than or equal to 1.7 * 10 ^-6(F/m ²) the image processing system of high electrostatic capacitance material.

Background technology

In the electronic photo image processing system, as the extensive usually Organophotoreceptor that adopts of the photoreceptor of picture supporting body.Fig. 5 is the layer structural model figure of an example of Organophotoreceptor.This Organophotoreceptor has stacked gradually the charge generating layer 12, charge transport layer 13, the sealer 14 that are made of organic material on metallic matrix 11.At this, the photographic layer of photoreceptor comprises charge generating layer 12, charge transport layer 13, the sealer 14 except metallic matrix 11.In addition, even when being provided with basalis on metallic matrix 11, photographic layer comprises charge generating layer 12, charge transport layer 13, sealer 14, does not promptly comprise metallic matrix 11 and basalis (not shown).Under for the situation of photoreceptor that does not have sealer 14, photographic layer is charge generating layer 12 and charge transport layer 13.

But the electronic photo image processing system along with the development of the digitizing of duplicating machine, printer, panchromaticization, high speed, expects that very duplicating machine, printer enter into light printing market.

But, in order to enter into printing market, the image processing system that can form the meticulous electrostatic latent image of height is absolutely necessary, and has in the Organophotoreceptor of electric charge generating mechanism in photoreceptor inside, before arriving photosensitive surface, produce the electric charge diffusion, have restriction aspect becoming more meticulous at height.

Therefore, as the electric charge diffusion is suppressed to the method that bottom line realizes that height becomes more meticulous, use has near the method for the amorphous silicon photoreceptor body of the mechanism that produces electric charge photosensitive surface, also causes people's attention (for example, with reference to TOHKEMY 2004-279902 communique) in recent years.

The amorphous silicon photoreceptor body shown in the layer structural model figure of Fig. 6, forms amorphous silicon photoreceptor layer (optical conductive layer) 15 basically on metallic matrix 11.The amorphous silicon photoreceptor body shown in the layer structural model figure of Fig. 6, stacks gradually electric charge trapping layer 15, charge generating layer 16, electric charge trapping layer 17 and superficial layer 18 basically on metallic matrix 11.At this, the photographic layer of amorphous silicon photoreceptor body is to remove layer behind the metallic matrix 11, be electric charge trapping layer 15, charge generating layer 16, electric charge trapping layer 17 and superficial layer 18 from photoreceptor.Amorphous silicon photoreceptor layer 15 is formed by amorphous silicon class materials such as a-Si, a-SiC, a-SiO, a-SiON, by formation such as for example aura (glow) discharge decomposition method, sputtering method, ECR method, vapour deposition methods.

In order to obtain high-resolution image, expectation wants high as the electrostatic capacitance of the per unit area of supporting body photographic layer.Particularly, the electrostatic capacitance of the per unit area of expectation photographic layer is more than or equal to 1.7 * 10 ^-6(F/m ²) high electrostatic capacitance.In this, amorphous silicon photoreceptor body (below be designated as the a-Si photoreceptor) is compared with Organophotoreceptor, dielectric constant is big about 3 times, thereby under the situation of photographic layer thickness identical (photoreceptor thickness is removed the gross thickness as the thickness of the metallic matrix of supporter), the electrostatic capacitance of the per unit area of photographic layer is big about 3 times.In addition,, need make the thickness attenuation of photographic layer, suppress the diffusion of electric charge in order to improve a repeatability.In the a-Si photoreceptor,, the thickness of photographic layer need be located at below the 50 μ m for the some repeatability that realizes allowing; In addition, in Organophotoreceptor,, the thickness of photographic layer need be located at below the 17 μ m in order to realize the some repeatability same with the a-Si photoreceptor.At this moment, each electrostatic capacitance as the per unit area of supporting body photographic layer is made as lower limit.According to above technical reason, be set at above-mentioned electrostatic capacitance 〉=1.7 * 10 ^-6(F/m ²).

The electrostatic capacitance of photographic layer is the value of measuring in order to following method.

The tabular photographic plate that preparation has the layer structure identical with actual photographic layer on metallic matrix.Make the little electrode of this tabular photographic plate contact gear ratio photographic plate, electrode is applied DC voltage.Monitor the electric current that flow through this moment, by resulting electric current being carried out time integral, obtain remaining in the quantity of electric charge q on the photographic layer.Carry out above-mentioned processing while the value that changes DC voltage, obtain the electrostatic capacitance C of photographic plate according to the variable quantity of quantity of electric charge q.

In the present example, measure, but, then also can measure with the photoreceptor of tubular as long as the shape of research electrode makes it to have the curvature identical with photoreceptor with the tabular photographic plate.

But, under the situation of using amorphous silicon photoreceptor body as high electrostatic capacitance (below be designated as the a-Si photoreceptor), can export very high meticulous image, and under situation about using as the Organophotoreceptor that hangs down electrostatic capacitance, with the image that generation be can't see bad " leaking white ".

As shown in Figure 7, " leak white " is such image deflects: to direct of travel (sense of rotation) the output shadow tone A of portion of the photosensitive surface picture pattern adjacent with the B of high concentration portion the time, the concentration of its boundary portion C becomes extremely light.About the direct of travel of photosensitive surface, comprise the B of high concentration portion the preceding and A of shadow tone portion after situation and on the contrary the A of shadow tone portion the preceding and B of high concentration portion after situation the two.

The inventor concentrates on studies to the occurrence cause of this " leak white ", thereby has known according to following mechanism (mechanism) and produce.Below, detailed content is described.

Fig. 8 is the figure of the electrostatic latent image current potential on the expression photoreceptor.In the present example, be the combination of photoreceptor-negative charging processing, image exposure, discharged-area development, unexposed portion is the (background: non-image portion) of background color portion.The sub-image current potential of the B of high concentration portion of Vl presentation video portion, the sub-image current potential of the A of shadow tone portion of Vh presentation video portion, Vd represents the sub-image current potential of non-image D.For this sub-image current potential is developed, when the developer carrier to developing apparatus is a development sleeve when applying developing bias voltage, toner is transferred to the image portion of photoreceptor from development sleeve, and sub-image is developed.This be because: pass through toner charge respectively, the potential difference (PD) of compensation DC voltage composition Vdc of developing bias voltage and the current potential Vl of image portion, be development contrast (contrast) current potential Vcont, and the potential difference (PD) of the DC voltage composition Vdc of developing bias voltage and the current potential Vh of image portion, be Vcont-h.

But, at the borderline region of A of shadow tone portion and the B of high concentration portion, because development contrast current potential Vcont and Vcont-h existence are poor, therefore, near photosensitive surface, except from development sleeve to the electric field of photoreceptor, also be formed with the circuitous electric field to high concentration portion from shadow tone portion.Figure 10 represents the electric field intensity of the borderline region of near the photosensitive surface high concentration portion and shadow tone portion.By this circuitous electric field, initial at developing procedure, be present near toner of borderline region and the toner that is present in shadow tone portion, according to electric field intensity shown in Figure 10, its major part is transferred to the sub-image of high concentration portion.

Along with the carrying out of developing procedure, when the development contrast current potential Vcont of the charge compensation high concentration portion of toner, the toner outermost layer current potential of high concentration portion is near Vdc.Therefore, the development contrast current potential Vcont of B of high concentration portion and the A of shadow tone portion, the difference of Vcont-h diminish, and above-mentioned circuitous electric field disappears.As a result, the toner of transferring to shadow tone portion from development sleeve can not shift to high concentration portion side, and is final, and all by toner charge compensation development contrast current potential, developing procedure finishes for shadow tone portion and high concentration portion.

But by before the developing regional, as shown in Figure 9 at the electric charge that is in toner during not with respect to the state of the sub-image potential compensation development contrast current potential of high concentration portion, the state that keeps circuitous electric field not disappear is constant, passes through developing regional fully.Therefore, enough toners are not transferred concerning the sub-image current potential of shadow tone portion, produce " leaking white " at the boundary portion C of A of shadow tone portion and the B of high concentration portion.In Fig. 9, be toner outermost layer current potential by the part of blacking with respect to the sub-image current potential.That is, toner outermost layer current potential is Vdc at the A of shadow tone portion, and B is Vs in high concentration portion.Therefore, in the B of high concentration portion, with respect to development contrast current potential Vcont, the potential difference (PD) Vs-Vl that compensates becomes quite little by toner is developed.

To can not show as " it is bad to charge " with the state that toner charge compensates the development contrast current potential like this.

Then, illustrate that " leak white " do not produce and the reason that produces in the a-Si photoreceptor in existing Organophotoreceptor.

The a-Si photoreceptor has following material behavior: compare specific inductive capacity big 3 times (the a-Si photoreceptor is about 10 with Organophotoreceptor, Organophotoreceptor is about 3.3), under situation, will have 3 times electrostatic capacitance of Organophotoreceptor with photographic layer thickness identical with Organophotoreceptor.

As a result, in the a-Si photoreceptor, satisfy the needed toner charge amount of development contrast current potential Vcont, Vcont-h, need be about 3 times of Organophotoreceptor.For example, when the toner that uses the carried charge identical with existing Organophotoreceptor develops, needing to compare about about 3 times toning dosage with Organophotoreceptor on the photoreceptor.

But present situation is the toning dosage that exists in development folder (nip) to be limited, thereby in the a-Si photoreceptor, can not the toning dosage that fully satisfies development contrast current potential Vcont be developed.Especially in order to compensate the development contrast current potential Vcont of the big high concentration portion of potential difference (PD), need very many quantities of electric charge.But,, thereby in the a-Si photoreceptor, can not compensate development contrast current potential Vcont because the toning dosage that develops that exists is limited in development folder.

As a result, take place " it is bad to charge ", it is bad to produce " leaking white " such image.

But, under the situation of Organophotoreceptor,, can access high-resolution image by making the filming of photographic layer thickness attenuation.Because Organophotoreceptor by the diffusion of the electric charge of photoinduction, therefore, need make the attenuation of photographic layer thickness in order to improve resolution at charge generating layer.And, be used to obtain the photographic layer thickness of the Organophotoreceptor of the resolution identical with the a-Si photoreceptor, can be below the 17 μ m as previously mentioned, when this photographic layer thickness conversion is become electrostatic capacitance, be lower limit 1.7 * 10 ^-6(F/m2).Therefore, under the situation of Organophotoreceptor, also carry out filming and electrostatic capacitance is made more than or equal to 1.7 * 10 ^-6(F/m2) high electrostatic capacitance equally also takes place with the a-Si photoreceptor " it is bad to charge ", and it is bad to produce " leaking white " such image.

Summary of the invention

The purpose of this invention is to provide and suppress the white image processing system of image leakage.

Another object of the present invention is that the bad image processing system of image that suppresses high concentration portion and shadow tone portion border is provided.

Another object of the present invention is to improve the bad image processing system of charging that is caused by toner charge to the sub-image current potential by developing.

Another object of the present invention is to provide and can carry out the image processing system that high meticulous image forms.

Another object of the present invention is to provide the electrostatic capacitance of using per unit area more than or equal to 1.7 * 10 ^-6The high electrostatic capacitance material of F/m2 is as the image processing system of photographic layer.

The invention provides a kind of image processing system, it is characterized in that, comprising: have the picture supporting body of photographic layer, the electrostatic capacitance of above-mentioned photographic layer per unit area is more than or equal to 1.7 * 10 ^-6F/m ²And developing apparatus, look like to develop to being formed at above-mentioned static with developer as supporting body with toner and carrier, on above-mentioned picture supporting body, form toner picture, this developing apparatus

Developer carrier with the above-mentioned developer of carrying, on this developer carrier, apply developing bias voltage, wherein, if the quantity of electric charge of the per unit weight of the above-mentioned toner picture on the above-mentioned picture supporting body is Q/M, unit is C/g, in the above-mentioned maximum concentration portion that can reach maximum concentration as the above-mentioned toner picture on the supporting body, the potential difference (PD) of the surface potential of above-mentioned picture supporting body and the flip-flop of above-mentioned developing bias voltage is Vcont, unit is V, the toner weight of the per unit area of the above-mentioned maximum concentration portion that can reach maximum concentration as the above-mentioned toner picture on the supporting body is M/S, and unit is g/m ²The thickness of toner layer is Lt in the maximum concentration portion of the above-mentioned toner picture on the above-mentioned picture supporting body, unit is m, the thickness of above-mentioned photographic layer is Ld, and unit is m, and the relative dielectric constant of above-mentioned toner layer is ε t, the relative dielectric constant of above-mentioned photographic layer is ε d, the specific inductive capacity of vacuum is ε 0, and unit is F/m, then satisfies following formula 1.

$\left|\frac{Q}{M}\right|\&GreaterEqual;\frac{0.95\&times;\mathrm{Vcont}}{\left(\frac{M}{S}\right)\&times;(\frac{{\mathrm{<figure-callout\; id="2"\; label="L\; t"\; filenames="C2006101392410033H2.png"\; state="\{\{state\}\}">L</figure-callout>}}_t}{2{\mathrm{\&epsiv;}}_0{\mathrm{\&epsiv;}}_t}+\frac{\mathrm{Ld}}{{\mathrm{\&epsiv;}}_0{\mathrm{\&epsiv;}}_d})}$ .... (formula 1)

The other objects and features of the invention are read following detailed description by the reference accompanying drawing and will be become clearer.

Description of drawings

Fig. 1 is the schematic configuration illustraton of model of the image processing system of embodiment 1.

Fig. 2 is the discussion result's of expression embodiment 1 (2-1) figure.

Fig. 3 is the key diagram of the toner particle diameter of embodiment 2 with respect to the LASER SPECKLE diameter.

Fig. 4 is the discussion result's of expression embodiment 2 figure.

Fig. 5 is the layer structural representation of Organophotoreceptor.

Fig. 6 is the layer structural representation of amorphous silicon photoreceptor.

Fig. 7 is the key diagram that leaks white phenomenon.

Fig. 8 is the figure of expression as the sub-image current potential on the supporting body.

Fig. 9 is the figure as the sub-image current potential on the supporting body after the expression development finishes.

Figure 10 is the key diagram of circuitous electric field.

Figure 11 is the discussion result's of expression embodiment 1 (2-2) figure.

Figure 12 is the discussion result's of expression embodiment 1 (2-2) figure.

Figure 13 is the discussion result's of expression embodiment 1 (2-3) figure.

Figure 14 is the discussion result's of expression embodiment 1 (2-3) figure.

Figure 15 is for obtaining the sketch map of the Faraday cylinder (faraday cage) that Q/M and M/S use.

Figure 16 is the sketch map of the device that uses for the DIELECTRIC CONSTANT t that obtains toner.

Embodiment

Below, illustrate in greater detail image processing system of the present invention in conjunction with the accompanying drawings.

[embodiment 1]

(1) the schematic configuration explanation of image processing system example

Fig. 1 is the schematic configuration illustraton of model of the image processing system of present embodiment.The image processing system of this example is to use amorphous silicon photoreceptor body (a-Si photoreceptor) as the electronic photo laser printer as photoreceptor supporting body, negative charging polarity, image exposure mode, discharged-area development mode, has the resolution of 1200dpi.

The 1st, the a-Si photoreceptor of cartridge type as shown in Figure 6, is formed with the photographic layer that is made of electric charge (electron) trapping layer 15, charge generating layer 16, electric charge (hole) trapping layer 17 and superficial layer 18 on aluminum substrate 11.The thickness Ld of photographic layer is 40 μ m (=40 * 10 ^-6M), the electrostatic capacitance of the per unit area of photographic layer is 2.2 * 10 ^-6(F/m ²).

Photoreceptor 1 is driven in rotation with predetermined speed in the clockwise direction of arrow, and its surface by charged device 2 uniform chargeds is-500V.

Then, carry out light image exposure L, form electrostatic latent image in sensitization dignity by 3 pairs of these charged treated sides of exposer.In the present example, exposer 3 is laser scanners.This scanner corresponding to the laser after the picture signal output modulation that is input to image processing system from not shown host apparatus such as personal computers, carries out scan exposure L at the charged face of photoreceptor 1.Thus, the potential decay of the bright portion of the sensitization dignity after the exposure by the current potential contrast of bright current potential after the dark portion current potential that is not exposed and the exposure, forms electrostatic latent image corresponding to the picture pattern of picture signal in sensitization dignity.In the present example, bright current potential is maximum concentration portion sub-image current potential Vl is-150V.Maximum concentration portion is the potential difference (PD) the best part of the flip-flop of developing bias voltage and the image portion current potential of electrostatic latent image (bright current potential), just closely knit image section.

Then, carry out discharged-area development as the toner picture by 4 pairs of these electrostatic latent images of developing apparatus.In the present example, developing apparatus 4 is developing apparatuss of binary visualization way.(carrier: particle diameter 35 μ m) two-component developer of Gou Chenging is rotatable developer carrier by toner (particle diameter is 7 μ m) and carrier.Be developed sleeve 4a carrying, and by this development sleeve 4a and be fixed and be configured in its inner magnetic roller 4b, to near photoreceptor 1 opposed opposed conveyance.Development sleeve 4a is applied to-the superposeed developing bias voltage of alternating component of the flip-flop Vdc of 350V, by sub-image current potential on the photoreceptor 1 and the potential difference (PD) between the development sleeve 4a, portion moves toner to image, electrostatic latent image as the toner picture by visual.

And, in the opposed transfer printing of photoreceptor 1 and transfer belt electrical equipment 5 portion, successively to the recording materials P that is transported to transfer printing portion in the constantly never illustrated paper advance mechanism of predetermined control portion, this toner picture of static printing.

Separate to be imported into fuser 6 by the recording materials P after the transfer printing portion from 1 of photoreceptor,, be discharged to outside the device as printed product in this hot pressing photographic fixing of accepting the unfixing toner picture.

In addition, the photoreceptor 1 after recording materials separate is removed residual attachments such as transfer printing remaining toners by clearer 7, and then, accept the blanket exposure of being undertaken and, supply with imaging repeatedly by electric initialization by prior exposure lamp 8.

(2) anti-leak-stopping is white

(2-1) its 1

In above-mentioned image processing system, studied the occurrence cause of " leaking white ".That is, studied weight M/S=0.5～0.8mg/cm with respect to the per unit area of the toner on the photoreceptor of maximum concentration portion ²(=5～8g/m ²), the quantity of electric charge Q/M of the per unit weight of the toner on the photoreceptor is changed, the occurrence cause of " leaking white " during the output shadow tone portion image adjacent with maximum concentration portion.

M/S is made as 0.5～0.8mg/cm ², be because this is the amount that also can guarantee enough image colors in maximum concentration portion.

In addition, the adjustment of Q/M and M/S is according to the additive kind of adding in toner and addition thereof, the adjustment of developer level is carried out on the adjustment of coating (coat) the agent kind of carrier surface coating and addition thereof, toner/carrier ratio, development sleeve.

In addition, the value of Q/M and M/S is by measuring the value that the toner on the photoreceptor obtains with following determination method.

In order easily to measure the toner on the photoreceptor, form in the action moment after on the photoreceptor toner being developed at image and cut off the power supply of image processing system.Use the Faraday cylinder that the metal cylinder that the diameter of axle is different is configured to coaxial inside and outside two-fold tube and is used for further toner being put into the filtrator (filter) of inner core that has shown in Figure 15, pneumatic (air) attracts the toner on the photoreceptor.The inner core of Faraday cylinder and urceolus insulation when putting into toner in filtrator, produce the electrostatic induction that is caused by toner charge amount Q.(KEITHLEY 616 DIGITAL ELECTROMETER) measure this sensed quantity of electric charge Q by the coulomb indicator, and divided by the toner weight M in the inner core, thereby obtain Q/M (μ C/g).In addition, measure the area S that is attracted on the photoreceptor, and remove toner weight M, thereby obtain M/S (mg/cm with this value ²).

In addition, for maximum concentration portion, the potential difference (PD) of bright current potential Vl of the flip-flop Vdc of developing bias voltage and photoreceptor is that development contrast current potential Vcont is 200V, for shadow tone portion, the potential difference (PD) of the current potential Vh of shadow tone portion of the flip-flop Vdc of developing bias voltage and photoreceptor is that development contrast current potential Vcont-h is 100V.

As mentioned above, the development contrast current potential is current potential Vl of image portion (perhaps Vh) on the developing location photoreceptor and the potential difference (PD) that is applied in the DC voltage composition Vdc of the developing bias voltage on the development sleeve.

Obtain in the following manner at the image portion current potential on the developing location photoreceptor: configuration surface pot on the position of developer is being set, measure the surface potential that image forms the photoreceptor in the action, obtain DC voltage composition Vdc poor of this surface potential and developing bias voltage.

Fig. 2 represents to discuss the result." leaking white " do not take place in the expression of zero among Fig. 2, and " leaking white " taken place in * expression.In addition, the picture shape device of present embodiment is the discharged-area development mode, uses the toner of negative charging, and therefore, the longitudinal axis of Fig. 2 is represented with the absolute value of the quantity of electric charge Q/M of the per unit weight of toner on the photoreceptor." leaking white " do not take place under following situation as shown in Figure 2:

M/S=0.5mg/cm ²(=5g/m ²) time, | Q/M| 〉=60 μ C/g (=60 * 10 ^-6C/g);

M/S=0.55mg/cm ²The time, | Q/M| 〉=53 μ C/g;

M/S=0.6mg/cm ²The time, | Q/M| 〉=47 μ C/g;

M/S=0.65mg/cm ²The time, | Q/M| 〉=43 μ C/g;

M/S=0.7mg/cm ²The time, | Q/M| 〉=39 μ C/g;

M/S=0.75mg/cm ²The time, | Q/M| 〉=35 μ C/g;

M/S=0.8mg/cm ²The time, | Q/M| 〉=32 μ C/g.

In addition, represent inequality 1 in each condition the right value be dotted line among Fig. 2, in table 1, record and narrate the value of representational M/S.

[table 1]

	0.5 mg/cm 2	0.55 mg/cm 2	0.6 mg/cm 2	0.65 mg/cm 2	0.7 mg/cm 2	0.75 mg/cm 2	0.8 mg/cm 2
								(formula 1) the right	60.0 μC/g	53.2 μC/g	47.7 μC/g	43.0 μC/g	39.1 μC/g	35.7 μC/g	32.8 μC/g

At this, formula 1 is by following formula definition.

$\left|\frac{Q}{M}\right|\&GreaterEqual;\frac{0.95\&times;\mathrm{Vcont}}{\left(\frac{M}{S}\right)\&times;(\frac{{\mathrm{<figure-callout\; id="2"\; label="L\; t"\; filenames="C2006101392410033H2.png"\; state="\{\{state\}\}">L</figure-callout>}}_t}{2{\mathrm{\&epsiv;}}_0{\mathrm{\&epsiv;}}_t}+\frac{\mathrm{Ld}}{{\mathrm{\&epsiv;}}_0{\mathrm{\&epsiv;}}_d})}$ ... (formula 1)

Wherein, if the quantity of electric charge of the per unit weight of the toner picture on the photoreceptor is Q/M (C/g), if the potential difference (PD) for the flip-flop of surface potential maximum concentration portion, photoreceptor of the toner picture on the photoreceptor and developing bias voltage is Vcont (V), the toner weight of per unit area of establishing the maximum concentration portion of the toner picture on the photoreceptor is M/S (g/m ²), if the thickness of toner layer is Lt (m) in the maximum concentration portion of the toner picture on the photoreceptor, the thickness of establishing photographic layer is Ld (m), and the relative dielectric constant of establishing toner layer is ε t, if the relative dielectric constant of photographic layer is ε d, the specific inductive capacity of establishing vacuum is ε 0 (F/m).

In addition, the unit of explanation is inconsistent in unit shown in the table 1 and the formula 1, and still, the dimension (dimension) on the left side and the right is consistent in formula 1, and the unit of table 1 must change the unit of an accepted way of doing sth 1.For example, with the M/S=0.5mg/cm of table 1 ²During substitution formula 1, must convert M/S=5g/m to ², the 60.0 μ C/g on the right of the formula 1 shown in the table 1 must convert 60.0 * 10 at this moment ^-6C/g.Certainly, the unit of Q/M also must be converted to (C/g).In addition, same as described above, for Q/M shown in Figure 2, the unit of M/S, when running into formula 1, also unit must be converted to (C/g), (g/m respectively ²).

As mentioned above, establish the absolute value of the quantity of electric charge Q/M that is developed in the per unit weight that looks like the toner on the supporting body the right more than or equal to (formula 1).Thus, can establish the current potential that forms by the toner that is developed on the picture supporting body, with respect to the development contrast current potential Vcont of the maximum concentration portion that needs most the quantity of electric charge, more than or equal to 95%.That is, in Fig. 9, for | Vl-Vs|/Vcont * 100 〉=95%.Bright current potential Vs is the surface potential as the toner layer on the supporting body after being developed by toner, is near the value of measuring developing location or developing location.The abduction of (formula 1) will be narrated in the back.

By being made as more than 95%, " the circuitous electric field " that is produced by the potential difference (PD) of the boundary vicinity of shadow tone/maximum concentration portion is little of negligible degree, and the toner that can suppress boundary vicinity moves.As a result, can solve the boundary portion of shadow tone portion and maximum concentration portion " leaking white ".

In addition, the toner weight M/S of per unit area by establishing maximum concentration portion on the picture supporting body is more than or equal to 0.5mg/cm ²And smaller or equal to 0.8mg/cm ²Thereby, also can guarantee enough image colors in maximum concentration portion.

In addition, establish maximum development contrast current potential Vcont with respect to maximum concentration portion, thereby can guarantee to be used to obtain the γ of enough GTGs, the high meticulous image output that can carry out clearly to show shadow tone more than or equal to 150V and smaller or equal to 250V.

And then the mean grain size by establishing toner is smaller or equal to 7 μ m, thereby realizes under the high-resolution situation reducing the LASER SPECKLE diameter, also can clearly form isolated sub-image, can carry out the high high meticulous image output of a repeatability.

The abduction of＜(formula 1) 〉

Be developed in the formed current potential Δ of the toner V (hereinafter referred to as charging potential) on the picture supporting body, represent with (formula 2) by deberthing loose measure journey.This Δ V is Fig. 9 | Vl-Vs|, the potential difference (PD) of the surface potential Vs of the toner picture after promptly developing in the maximum concentration portion as toner picture on the surface potential Vl of the picture supporting body before developing in the maximum concentration portion of toner picture on the supporting body and the picture supporting body.

First of the right is the current potential by the generation of the electric charge of toner itself, and second is illustrated in toner charge and as the current potential that generates between the supporting body basic unit.

$\mathrm{\&Delta;V}=(\frac{{\mathrm{<figure-callout\; id="2"\; label="L\; t"\; filenames="C2006101392410033H2.png"\; state="\{\{state\}\}">L</figure-callout>}}_t}{2{\mathrm{\&epsiv;}}_0{\mathrm{\&epsiv;}}_t}\&times;\frac{Q}{M}\&times;\frac{M}{S})+(\frac{L_d}{{\mathrm{\&epsiv;}}_0{\mathrm{\&epsiv;}}_d}\&times;\frac{Q}{M}\&times;\frac{M}{S})$ ... (formula 2)

Bad in order to improve the charging that produces by circuitous electric field at the boundary vicinity of shadow tone/high concentration portion, need establish the absolute value of charging potential Δ V of the maximum concentration portion of the most difficult charging, with the development contrast current potential Vcont of maximum concentration portion about equally.

The process inventor's conscientiously research as can be known, the reason that is made as about equally is, owing to also the toner that exists on the photoreceptor is worked with the adhesion of photoreceptor, therefore, inhibition is moved conditions needed by the toner that circuitous electric field causes, the absolute value of charging potential Δ V that is maximum concentration portion is more than or equal to 95% of the development contrast current potential Vcont of maximum concentration portion, promptly

| charging potential Δ V| 〉=Vcont * 0.95... (formula 3)

In other words,

|Vl-Vs|≥Vcont×0.95

Therefore, with (formula 2) substitution (formula 3), the toner charge amount Q/M as the per unit weight on the supporting body is put in order, thereby derived (formula 1).

In Fig. 2, relatively leak white hair and give birth to behind situation and the dotted line as can be known, if absolute value greater than the Q/M of the value on the dotted line " leaking white " does not take place then.The dotted line of Fig. 2 is equivalent to the equal sign in the formula 1.Therefore, the scope on the dotted line of Fig. 2 is equivalent to the scope of formula 1.

Each parameter value that uses when calculating the right of (formula 1) is as follows.Value beyond the specific inductive capacity of vacuum is a measured value.

The specific inductive capacity of vacuum: ε 0=8.854 * 10 ^-12(F/m);

The relative dielectric constant ε d:10 of photographic layer;

The relative dielectric constant ε t:2.5 of toner layer in the maximum concentration portion of the toner picture on the photoreceptor;

The thickness Lt of toner layer in the maximum concentration portion of the toner picture on the photoreceptor:

8.04μm(M/S＝0.5mg/cm ²)

8.72μm(M/S＝0.55mg/cm ²)

9.39μm(M/S＝0.6mg/cm ²)

10.07μm(M/S＝0.65mg/cm ²)

10.74μm(M/S＝0.7mg/cm ²)

11.42μm(M/S＝0.75mg/cm ²)

12.09μm(M/S＝0.8mg/cm ²)

For the unit (μ m) of the thickness of above-mentioned toner layer, also must the unit of being converted into (m) when substitution formula 1.That is, be under the situation of 8.04 μ m during substitution formula 1 at the thickness of toner layer, must be made as 8.04 * 10 ^-6M.

Assay method to employed each parameter of present embodiment describes.

The thickness Ld of＜photographic layer 〉

The tabular photographic plate that preparation has the layer structure identical with actual photographic layer on metallic matrix.Measure the thickness of implementing the photographic layer front and back with film thickness gauge,, obtain the thickness Ld of photoreceptor by calculating its difference.

The relative dielectric constant ε d of＜photographic layer 〉

The tabular photographic plate that preparation has the layer structure identical with actual photographic layer on metallic matrix.Make the little electrode of this tabular photographic plate contact gear ratio photographic plate, electrode is applied DC voltage.Monitor the electric current that flow through this moment, by resulting electric current being carried out time integral, obtain remaining in the quantity of electric charge q on the photographic layer.Carry out above-mentioned processing while the value that changes DC voltage, obtain the electrostatic capacitance C of photographic plate according to the variable quantity of quantity of electric charge q.The electrostatic capacitance C that use determines, electrode area S and with the photoreceptor thickness Ld that said method is obtained obtain the DIELECTRIC CONSTANT of photoreceptor according to C=ε S/Ld.With the specific inductive capacity of the photoreceptor obtained DIELECTRIC CONSTANT 0, obtain the relative dielectric constant ε d of photoreceptor divided by vacuum.

In the present example, measure, but, then also can measure with the photoreceptor of tubular as long as the shape of research electrode makes it to have the curvature identical with photoreceptor with the tabular photographic plate.

The thickness Lt of＜toner layer 〉

Use 3 d shape testing laser microscope (keyence makes VK-9500), measure the height that on the photoreceptor position of toner layer is arranged and do not have the position of toner layer, obtain toner bed thickness Lt by calculating its difference.

The relative dielectric constant ε d of＜toner layer 〉

In the device of Figure 16, the potential change waveform when measuring on/off switch is obtained the DIELECTRIC CONSTANT t of toner according to this waveform.Detailed content below is described.

The device of Figure 16, with the thickness of about 30mm clamping toner equably, with lower electrode ground connection, upper electrode is connected on the high-voltage power supply via switch and resistance R (30M Ω) between 2 smooth electrodes.In order to write down the upper electrode current potential, surface potential meter and oscillograph near upper electrode, have been disposed.

In this device, be that on-state applies hundreds of V to the upper electrode current potential by making switch, measure the upcurve of upper electrode current potential.

(a) represent, therefore, obtains the DIELECTRIC CONSTANT of toner layer according to the upcurve of upper electrode current potential by formula with electric charge transport equation formula for the DIELECTRIC CONSTANT of toner layer.L is the toner layer height, and S is an electrode area, and R is power supply-switch room resistance, and Vi is a supply voltage, and VT is the upper electrode current potential, and τ is the surge time of toner layer.

... (formula is a)

The differential coefficient of voltage VT is obtained according to the decline curve (passage of time of the upper electrode current potential that switch is measured when on-state becomes off-state) of the upper electrode current potential that determines in advance.

In addition, the surge time of toner layer can be calculated by (formula b), and therefore, the differential coefficient that uses the decline curve according to the upper electrode current potential to draw is obtained the surge time τ of the toner layer of voltage VT.

$\mathrm{\&tau;}=-\frac{V}{(\mathrm{dV}/\mathrm{dt})}$ ... (formula b)

With the DIELECTRIC CONSTANT of the toner layer that draws like this DIELECTRIC CONSTANT 0, thereby obtain the relative dielectric constant ε t of toner layer divided by vacuum.

(2-2) its 2

And then, studied will be with respect to the development contrast current potential Vcont of maximum concentration portion the occurrence cause of " leaking white " during as following condition.That is, studied weight M/S=0.5～0.8mg/cm with respect to the per unit area of toner on the photoreceptor of maximum concentration portion ², the quantity of electric charge Q/M of the per unit weight of toner on the photoreceptor is changed, the occurrence cause of " leaking white " during the output shadow tone portion image adjacent with maximum concentration portion.

Except development contrast current potential Vcont, be the condition same with (2-1) with respect to maximum concentration portion.

Development contrast current potential Vcont:150V, 250V with respect to maximum concentration portion

Making the maximum development contrast current potential Vcont with respect to maximum concentration portion is 150V～250V, be for be suitable for guaranteeing being used to obtain can with print corresponding GTG.

Figure 11 represents the discussion result of Vcont=150V, and Figure 12 represents the discussion result of Vcont=250V.Among the figure zero expression " leaks white " not produce, and " leaking white " taken place in * expression.In addition, the image processing system of present embodiment is the discharged-area development mode, uses the toner of negative charging, and therefore, the longitudinal axis of Figure 11, Figure 12 is represented with the absolute value of the quantity of electric charge Q/M of the per unit weight of toner on the photoreceptor.

" leaking white " when Vcont=150V, do not take place under following situation as shown in Figure 11:

M/S=0.5mg/cm ²The time ... | Q/M| 〉=45 μ C/g

M/S=0.55mg/cm ²The time ... | Q/M| 〉=39 μ C/g

M/S=0.6mg/cm ²The time ... | Q/M| 〉=35 μ C/g

M/S=0.65mg/cm ²The time ... | Q/M| 〉=32 μ C/g

M/S=0.7mg/cm ²The time ... | Q/M| 〉=29 μ C/g

M/S=0.75mg/cm ²The time ... | Q/M| 〉=26 μ C/g

M/S=0.8mg/cm ²The time ... | Q/M| 〉=24 μ C/g

In addition, the right value of (formula 1) is dotted line among Figure 11 when representing each Vcont=150V, and table 2 is recorded and narrated the value of representational M/S.The unit of explanation is inconsistent in unit shown in the table 2 and the formula 1, but the dimension on the left side and the right is consistent in formula 1, and the unit of table 2 must change the unit of an accepted way of doing sth 1.For example, with the M/S=0.5mg/cm of table 2 ²During substitution formula 1, must be made as M/S=5mg/m ², the right 45.0 μ C/g of the formula 1 shown in the table 2 must be made as 45.0 * 10 at this moment ^-6C/g.

[table 2]

	0.5 mg/cm 2	0.55 mg/cm 2	0.6 mg/cm 2	0.65 mg/cm 2	0.7 mg/cm 2	0.75 mg/cm 2	0.8 mg/cm 2
								(formula 1) the right	45.0 μC/g	39.9 μC/g	35.8 μC/g	32.3 μC/g	29.3 μC/g	26.8 μC/g	24.6 μC/g

In Figure 11, relatively leak white hair and give birth to behind situation and the dotted line as can be known, if absolute value greater than the Q/M of the value on the dotted line " leaking white " does not take place then.

Then, Vcont=250V is described.

" leaking white " when Vcont=250V, do not take place under following situation as shown in Figure 12:

M/S=0.5mg/cm ²The time ... | Q/M| 〉=75 μ C/g

M/S=0.55mg/cm ²The time ... | Q/M| 〉=66 μ C/g

M/S=0.6mg/cm ²The time ... | Q/M| 〉=59 μ C/g

M/S=0.65mg/cm ²The time ... | Q/M| 〉=53 μ C/g

M/S=0.7mg/cm ²The time ... | Q/M| 〉=48 μ C/g

M/S=0.75mg/cm ²The time ... | Q/M| 〉=44 μ C/g

M/S=0.8mg/cm ²The time ... | Q/M| 〉=41 μ C/g

In addition, the right value of (formula 1) is dotted line among Figure 12 when representing each Vcont=250V, and table 3 is recorded and narrated the value of representational M/S.For the unit of table 3, unit that also must change formula 1 when actual substitution formula 1.

[table 3]

0.5 mg/cm 2

0.55 mg/cm 2

0.6 mg/cm 2

0.65 mg/cm 2

0.7 mg/cm 2

0.75 mg/cm 2

0.8 mg/cm 2

(formula 1) the right

75.0 μC/g

66.6 μC/g

59.6 μC/g

53.8 μC/g

48.9 μC/g

44.6 μC/g

41.0 μC/g

In Figure 12, relatively leak white hair and give birth to behind situation and the dotted line as can be known, if absolute value greater than the Q/M of the value on the dotted line " leaking white " does not take place then.

The value of each parameter of using when calculating the right of (formula 1) is identical with (2-1) except Vcont.

(2-3) its 3

The occurrence cause of " leaking white " when also having studied under Vcont=150V thickness with photographic layer as following condition.That is, studied weight M/S=0.5～0.8mg/cm with respect to the per unit area of toner on the photoreceptor of maximum concentration portion ², the quantity of electric charge Q/M of the per unit weight of toner on the photoreceptor is changed, the occurrence cause of " leaking white " during the output shadow tone portion image adjacent with maximum concentration portion.Except the thickness and Vcont of photographic layer, carry out with the condition identical with (2-1).

As thickness Ld:15 μ m, the 20 μ m of photographic layer, the representation example that 30 μ m, 52 μ m discuss the result, Figure 13 represents the result of the thickness 52 μ m of photographic layer, and Figure 14 represents the result of the thickness 15 μ m of photographic layer.Among the figure zero expression " is leaked white " and is not taken place, and " leaking white " taken place in * expression.In addition, the longitudinal axis of Figure 13, Figure 14 is represented with the absolute value of the quantity of electric charge Q/M of the per unit weight of toner on the photoreceptor.For the thickness of photographic layer, when substitution formula 1, also unit must be converted to (m) from (μ m).The equation of the dotted line expression 1 of Figure 13, Figure 14.

" leaking white " when the thickness of photographic layer is 52 μ m, do not take place under following situation as shown in Figure 13:

M/S=0.5mg/cm ²The time ... | Q/M| 〉=37 μ C/g

M/S=0.55mg/cm ²The time ... | Q/M| 〉=33 μ C/g

M/S=0.6mg/cm ²The time ... | Q/M| 〉=29 μ C/g

M/S=0.65mg/cm ²The time ... | Q/M| 〉=26 μ C/g

M/S=0.7mg/cm ²The time ... | Q/M| 〉=24 μ C/g

M/S=0.75mg/cm ²The time ... | Q/M| 〉=22 μ C/g

M/S=0.8mg/cm ²The time ... | Q/M| 〉=20 μ C/g

In addition, the thickness of expression photographic layer when being 52 μ m (formula 1) the right value be dotted line among Figure 13, the value of the representational M/S of table 4 record.

[table 4]

	0.5 mg/cm 2	0.55 mg/cm 2	0.6 mg/cm 2	0.65 mg/cm2	0.7 mg/cm 2	0.75 mg/cm 2	0.8 mg/cm 2
								(formula 1) the right	37.1 μC/g	33.0 μC/g	29.7 μC/g	26.9 μC/g	24.5 μC/g	22.5 μC/g	20.7 μC/g

In Figure 13, relatively leak white hair and give birth to behind situation and the dotted line as can be known, if absolute value greater than the Q/M of the value on the dotted line " leaking white " does not take place then.

Below, the thickness that photographic layer is described is the situation of 15 μ m.

" leaking white " when the photoreceptor thickness is 15 μ m, do not take place under following situation as shown in Figure 14:

M/S=0.5mg/cm ²The time ... | Q/M| 〉=80 μ C/g

M/S=0.55mg/cm ²The time ... | Q/M| 〉=70 μ C/g

M/S=0.6mg/cm ²The time ... | Q/M| 〉=62 μ C/g

M/S=0.65mg/cm ²The time ... | Q/M| 〉=55 μ C/g

M/S=0.7mg/cm ²The time ... | Q/M| 〉=49 μ C/g

M/S=0.75mg/cm ²The time ... | Q/M| 〉=44 μ C/g

M/S=0.8mg/cm ²The time ... | Q/M| 〉=40 μ C/g

In addition, the right value of (formula 1) was dotted line among Figure 14 when expression photoreceptor thickness was 15 μ m, the value of the representational M/S of table 5 record.

[table 5]

	0.5 mg/cm 2	0.55 mg/cm 2	0.6 mg/cm 2	0.65 mg/cm 2	0.7 mg/cm 2	0.75 mg/cm 2	0.8 mg/cm 2
								(formula 1) the right	81.2 μC/g	70.7 μC/g	62.3 μC/g	55.2 μC/g	49.4 μC/g	44.5 μC/g	40.3 μC/g

In Figure 14, relatively leak white hair and give birth to behind situation and the dotted line as can be known, if absolute value greater than the Q/M of the value on the dotted line " leaking white " does not take place then.

The value of each parameter of using when calculating the right of (formula 1) is identical with (2-1) except that the thickness of photoreceptor and Vcont.

When being 20 μ m, 30 μ m, the thickness of photographic layer also as can be known, at the absolute value of Q/M " leaking white " do not take place during greater than the right value of (formula 1).

More than, the absolute value of toner charge amount Q/M by making the per unit weight on the photoreceptor is more than or equal to the right of (formula 1), even use under the situation of the big amorphous silicon photoreceptor body of electrostatic capacitance, also can improve bad the preventing of charging and " leak white ", obtain high meticulous image.

[embodiment 2]

In the present embodiment, except the structure of embodiment 1, also explanation reduces the example of toner particle diameter.

As the background technology that reduces the toner particle diameter, the high precise image output of ruling printing market for the sub-photo of electricity consumption is arranged, and reduce laser spot diameter to seek high-resolution method.But,, need reduce the toner particle diameter for high-resolution electrostatic latent image is visual in development step more accurately.

Therefore, as an example, the image processing system with resolution 2400dpi is described in the present embodiment.

In the present embodiment, for obtaining the resolution of 2400dpi, used the exposer 3 of the blue laser that is equipped with the about 420nm of emission wavelength.

The spot diameter of 2400dpi is about 10.6 μ m, in order to carry out visual to the point-like electrostatic latent image more accurately in development step and to reproduce, has used the toner of particle diameter as about 1/3, the promptly 3.5 μ m of spot diameter.

Make the toner particle diameter be 1/3 of spot diameter be because, in order to reproduce the point-like sub-image, preferably be configured to hexagonal configuration with respect to laser spot diameter a as shown in Figure 3, for this reason, needed toner particle diameter b is about (a/3).

It is identical with embodiment 1 that the image of image processing system forms action, so detailed.

With the embodiment 1 identical occurrence cause of studying " leaking white ".That is, studied weight M/S=0.5～0.8mg/cm with respect to the per unit area of toner on the photoreceptor of maximum concentration portion ², the quantity of electric charge Q/M of the per unit weight of toner on the photoreceptor is changed, the occurrence cause of " leaking white " during the output shadow tone portion image adjacent with maximum concentration portion.

Development contrast current potential Vcont with respect to maximum concentration portion is 200V, is 100V with respect to the development contrast current potential Vcont-h of shadow tone portion.

The adjustment of Q/M and M/S is undertaken by kind, addition and toner/carrier ratio of adjusting the toner adjuvant.

Fig. 4 represents to discuss the result.Among the figure zero expression " is leaked white " and is not taken place, and " leaking white " taken place in * expression.In addition, because the image processing system of present embodiment has used the toner of negative charging, therefore, the longitudinal axis is represented with the absolute value of the quantity of electric charge Q/M of the per unit weight of toner on the photoreceptor.As shown in Figure 4, under following situation, do not produce " leaking white ":

M/S=0.5mg/cm ²The time ... | Q/M| 〉=61 μ C/g

M/S=0.55mg/cm ²The time ... | Q/M| 〉=54 μ C/g

M/S=0.6mg/cm ²The time ... | Q/M| 〉=48 μ C/g

M/S=0.65mg/cm ²The time ... | Q/M| 〉=43 μ C/g

M/S=0.7mg/cm ²The time ... | Q/M| 〉=39 μ C/g

M/S=0.75mg/cm ²The time ... | Q/M| 〉=36 μ C/g

M/S=0.8mg/cm ²The time ... | Q/M| 〉=33 μ C/g

In addition, represent each condition (formula 1) the right value be dotted line among Fig. 4, table 6 is recorded and narrated the value of representational M/S.

[table 6]

	0.5 mg/cm 2	0.55 mg/cm 2	0.6 mg/cm 2	0.65 mg/cm 2	0.7 mg/cm 2	0.75 mg/cm 2	0.8 mg/cm 2
								(formula 1) the right	61.4 μC/g	54.5 μC/g	48.8 μC/g	44.0 μC/g	39.9 μC/g	36.4 μC/g	33.4 μC/g

In Fig. 4, relatively leak white hair and give birth to behind situation and the dotted line as can be known, if absolute value greater than the Q/M of the value on the dotted line " leaking white " does not take place then.

Each numerical value that uses when calculating (formula 1) the right is as follows, and the value except that the specific inductive capacity of vacuum is a measured value.

The specific inductive capacity of vacuum: ε 0=S.854 * 10 ^-12(F/m)

Relative dielectric constant ε d:10 on the photoreceptor

The relative dielectric constant ε t:2.5 of toner layer

Toner bed thickness Lt on the photoreceptor:

7.4μm(M/S＝0.5mg/cm ²)

8.07μm(M/S＝0.55mg/cm ²)

8.75μm(M/S＝0.6mg/cm ²)

9.42μm(M/S＝0.65mg/cm ²)

10.10μm(M/S＝0.7mg/cm ²)

10.77μm(M/S＝0.75mg/cm ²)

11.45μm(M/S＝0.8mg/cm ²)

And then, be after discussing under the condition of 150V, 250V, not produce when the absolute value of Q/M is greater than (formula 1) the right value as can be known " leaking in vain " at the development contrast current potential Vcont of maximum concentration portion.

And then, be after discussing under the condition of 15 μ m, 20 μ m, 30 μ m, 52 μ m, not produce when the absolute value of Q/M is greater than (formula 1) the right value as can be known " leaking in vain " at photoreceptor thickness Ld.

Also have, can tackle various resolution ground after discussing under the following toner particle diameter condition, do not produce when the absolute value of Q/M is greater than (formula 1) the right value as can be known " leaking white ".

Toner particle diameter: 5 μ m, 3 μ m, 1.8 μ m

Toner particle diameter of the present invention is the weight average particle diameter that is obtained by following determination method.Generation has added the electrolytic aqueous solution 100-150ml (for example about 1%NaCl aqueous solution) of several ml interfacial agents (preferably alkyl benzene sulfonate), adds toner 2～20mg, carries out several minutes dispersion treatment with ultrasonic disperser.Use coulter counter (coulter company makes TA-II) to measure this solution, thereby obtain weight average particle diameter.

More than, except using the big amorphous silicon photoreceptor body of electrostatic capacitance, even under the situation that reduces the toner particle diameter, the absolute value that also makes the toner charge amount Q/M that looks like the per unit weight on the supporting body is more than or equal to (formula 1) the right.Thus, can improve bad the preventing of charging and " leak white ", obtain high meticulous image.

In embodiment 1 and 2, use the amorphous silicon photoreceptor body as the picture supporting body.But the invention is not restricted to amorphous silicon, the electrostatic capacitance of using per unit area is more than or equal to 1.7 * 10 ^-6(F/m ²), the image processing system of electrostatic capacitance is big picture supporting body is also effective.That is, the absolute value of the toner charge amount Q/M by making the per unit weight on such picture supporting body can improve bad the preventing of charging and " leak white " more than or equal to (formula 1) the right, obtains high meticulous image.

As previously mentioned, even under the situation of Organophotoreceptor, carry out filming and make electrostatic capacitance more than or equal to 1.7 * 10 ^-6(F/m ²) the photoreceptor of high electrostatic capacitance, can improve bad the preventing of charging too and " leak white ", obtain high meticulous image.

In addition, in embodiment 1 and 2, use the color toner of the relative dielectric constant of toner layer as ε t=2.5.But the invention is not restricted to this value.In the black toner of the higher carbon of the relative dielectric constant that comprises toner layer, the absolute value of toner charge amount Q/M that also can be by making the per unit weight of picture on the supporting body is more than or equal to (formula 1) the right, " leak white " thereby improve bad the preventing of charging, obtain high meticulous image.

Such as already explained, about Q/M, the M/S that puts down in writing in embodiment and the accompanying drawing, the unit of Lt, Ld, under unit and the different situation shown in the formula 1, unit must be changed the unit of an accepted way of doing sth 1 during substitution formula 1.

Claims (6)

1. an image processing system is characterized in that, comprising:

Have the picture supporting body of photographic layer, the electrostatic capacitance of above-mentioned photographic layer per unit area is more than or equal to 1.7x10 ^-6F/m ²And

Developing apparatus, look like to develop to being formed at above-mentioned static as supporting body with the developer with toner and carrier, form the toner picture on above-mentioned picture supporting body, this developing apparatus has the developer carrier of the above-mentioned developer of carrying, on this developer carrier, apply developing bias voltage

Wherein, if the quantity of electric charge of the per unit weight of the above-mentioned toner picture on the above-mentioned picture supporting body is Q/M, unit is C/g, the potential difference (PD) that above-mentioned concentration as the above-mentioned toner picture on the supporting body can reach the flip-flop of surface potential in the highest maximum concentration portion, above-mentioned picture supporting body and above-mentioned developing bias voltage is Vcont, unit is V, the toner weight of the per unit area of the above-mentioned maximum concentration portion of the above-mentioned toner picture on the above-mentioned picture supporting body is M/S, and unit is g/m ²The thickness of toner layer is Lt in the above-mentioned maximum concentration portion of the above-mentioned toner picture on the above-mentioned picture supporting body, unit is m, the thickness of above-mentioned photographic layer is Ld, and unit is m, and the relative dielectric constant of above-mentioned toner layer is ε t, the relative dielectric constant of above-mentioned photographic layer is ε d, the specific inductive capacity of vacuum is ε 0, and unit is F/m, then satisfies following formula 1

$\left|\frac{Q}{M}\right|\&GreaterEqual;\frac{0.95\&times;\mathrm{Vcont}}{\left(\frac{M}{S}\right)\&times;(\frac{L_t}{2{\mathrm{\&epsiv;}}_0{\mathrm{\&epsiv;}}_t}+\frac{\mathrm{Ld}}{{\mathrm{\&epsiv;}}_0{\mathrm{\&epsiv;}}_d})}$ ... (formula 1).

2. image processing system according to claim 1 is characterized in that:

Above-mentionedly comprise uncrystalline silicon as supporting body.

3. image processing system according to claim 1 is characterized in that:

The toner weight of the per unit area of the above-mentioned maximum concentration portion of the above-mentioned toner picture on the above-mentioned picture supporting body is more than or equal to 0.5mg/cm ²And smaller or equal to 0.8mg/cm ²

4. according to claim 1 or 3 described image processing systems, it is characterized in that:

Vcont satisfies 150V≤Vcont≤250V.

5. according to the image processing system described in the claim 1, it is characterized in that:

The weight average particle diameter of toner is smaller or equal to 7 μ m.

6. an image processing system is characterized in that, comprising:

Have the picture supporting body of photographic layer, the electrostatic capacitance of above-mentioned photographic layer per unit area is more than or equal to 1.7 * 10 ^-6F/m ²And

Developing apparatus, look like to develop to being formed at above-mentioned static as supporting body with the developer with toner and carrier, form the toner picture on above-mentioned picture supporting body, this developing apparatus has the developer carrier of the above-mentioned developer of carrying, on this developer carrier, apply developing bias voltage

Wherein, if it is Vcont that above-mentioned concentration as the above-mentioned toner picture on the supporting body can reach the potential difference (PD) of the flip-flop of surface potential in the highest maximum concentration portion, above-mentioned picture supporting body and above-mentioned developing bias voltage, unit is V, the surface potential of above-mentioned picture supporting body in the above-mentioned maximum concentration portion of the above-mentioned toner picture on the above-mentioned picture supporting body, before developing is V1, unit is V, the surface potential of above-mentioned toner picture in the above-mentioned maximum concentration portion of the above-mentioned toner picture on the above-mentioned picture supporting body, after developing is Vs, unit is V, then satisfies

|V1-Vs|≥Vcont×0.95。

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