JPS58102945A - Electrostatic recording medium - Google Patents

Abstract

PURPOSE:To prevent the occurence of spots and voids by laminating a high resistance layer, a low resistance layer and a dielectric layer on an internal metallic support to form the surface of the rotary cylinder of an electrostatic recording device for forming an electrostatic latent image. CONSTITUTION:A metallic drum 11 for a rotary cylinder for forming an electrostatic latent image is coated with a high resistance layer having 3X10<9>OMEGA.cm volume resistivity in 100mum thickness, a lower resistance layer having 10<7>OMEGA/cm<2> surface resistance in 10mum thickness and a dielectric layer 14 of a substance having 32 dielectric constant in 20mum thickness in succession to form a recording medium 1. The medium 1 is charged to +450V surface potential with a uniform charging corotron (not shown), and the potential of both ends of the layer 13 is set to -150V prescribed value. In accordance with a signal, -150V voltage is applied to a noncontact pin electrode 3. Thus, medium discharge is repeated several times in place of a single large discharge, and a fine latent image free from spots and voids is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical field of SO generation The present invention relates to an electrostatic recording medium used in an electrostatic recording device. This article concerns electrostatic recording media that can be transferred to paper.

(2) Prior Art and Disadvantages The present applicant has already proposed an electrostatic recording method capable of transferring onto paper, as shown in $111iA.

In this method, a single electric element 1b is constructed on a metal drum 11,
ζO# Discharge to the electric body Il & 1b! 2, p is uniformly positively charged, and then a negative voltage vp is applied to the bottle electrode 5, which is arranged in a non-contact manner with respect to the recording drum 1 according to the character pattern.
is applied, and an electrostatic image is formed by discharge. after that,
The image is developed by a magnetic brush developing device 4, and transferred to a normal image 6 by a corona discharger 5. The recording drum 1 used in this method is conventionally made of a metal drum 1a with a ferroelectric material 1b formed thereon. However, in this type of electrostatic recording medium, the printing quality deteriorates because of the 30 dots of the bin electrode, and there are many abnormally large # grooves, so-called spots, missing prints, and so-called voids. was there.

(9) When the dielectric film 1b, which is the recording layer, is formed on the metal drum 1 and the dielectric film 1b is formed on the metal drum 1 in the method of bringing the pin electrode 5 into contact with the electrostatic recording medium, if there is a defect such as a pinhole in the recording layer, A spark discharge occurs between the bottle electrode 5 and the metal drum 1a. Rounding to solve this, 4IIi by the applicant
As shown in the invention of llll No. 152753/1983,
A semiconducting intermediate layer having a volume resistivity of 10 to 1 oaΩ is formed on a metal drum to a thickness of 10 to several tens of microliters, and a dielectric material JLLB serving as a recording layer is formed on top of this to form a 92-layer structure drum. be done. However, when this drum is used in the electrostatic recording medium shown in Figure 1, it is possible that, as in the case of using only a dielectric film, spots or voids may occur. Similarly, there are 6 drawbacks that affect printing quality.
Nineteen.

(3) An object of the present invention is to provide an electrostatic recording medium capable of forming fine scratches without voids or spots.

(4) Structure of the Invention In order to couple the above-mentioned target, the electrostatic recording fabric of the present invention is used in the electrostatic recording device, and is placed on a conductive support between the round recording layer and the bottle electrode. In an electrostatic recording medium capable of forming a static electric potential during a discharge and then being transferred onto plain paper, the recording layer comprises a high resistance layer (the lower layer) and a resistance layer set to a predetermined potential related to the discharge time.

Furthermore, a fermentation material layer for forming an electrostatic latent image (discharge) is provided thereon.

(5) Embodiments of the Invention The present invention will be explained in detail. First, we investigated the image formation mechanism in electrostatic recording in detail, and found that the initial electron emission from the tip of the bottle electrode and the subsequent electron avalanche multiplication phenomenon are important in latent image formation. The cause of the void is the insufficient supply of initial electrons from the tip of the bottle electrode. It became clear that the cause of the spot generation was excessive current due to electron avalanche multiplication.

Field emission from the tip of the initial electron supply line bottle electrode 91
It has been found that the supply amount n of insects p per unit time is approximately expressed by the following equation when the electric field strength at the tip of the bottle electrode is within the electric field range used in ordinary Seidenki.

An-AE+B (5QMV/” <E<50MV/
u) (1) However, A: Proportionality coefficient B: Constant E;
It has become clear that the electric field M9 and the discharge current 1 flowing during discharge are approximately expressed by the following equation.

leωCVeo (2)
9 points, -=2π1/T (T: transfer time of io/) C-πi, C・(recording layer capacity) r・: bottle electrode medium diameter Co; recording layer unit area p capacity Vao; It can be seen that in order to suppress the difference between the sickle voltage and the discharge starting pressure, that is, the latent image intensity, and the spot, it is sufficient to make Vao smaller by 9 Ct. and ζroga, Voo
If the value of the latent image is made small, the initial number of electrons in the water wheel will be small in equation (α), and the latent image stiffness will be small, which will cause the void O to be generated.

The recording layer capacitance C was changed with a voltage of 600 V, so I searched for conditions that would not cause O to occur. Nineteen.

However, according to research on the development mechanism, the required recording layer capacity is 50
It is known that it is greater than QPF/lxj. Oh.

9. Threshold to which the latent image forming pulse is applied, Q is 50PF
/aIj or less, the discharge starting voltage including the layer becomes high (and causes voids to occur.When the discharge current flows, only the turtle's CI is 50PF/- or less, and the other parts are C. It is thought that if an electrostatic body is constructed with an OPF of 6Ω or more, a good latent image with no voids will be formed at the spot.

FIG. 2 is an explanatory diagram of the basic configuration of the main parts of the present invention.

In the same figure, a capacity of 50P is placed on the metal support 11 from the bottom layer.
A high-resistance layer 12 with a volume resistivity of 10 to 10 Ω of less than FA- is provided, and a surface resistance of 10 to 10" Ω is provided thereon.
/ 1s resistance layer at the mouth and a capacitance of 300PF~ on it
The dielectric layer 14 described above has a 95-group structure, and the resistance layer 15
By connecting both ends of 0 to the metal support 11, a discharge is made to the pin voltage 4 through the 15-hole 116t, and at the time of death, the capacity is 50PF/<- or less. Otherwise, it is 500PF/i. -It is round and has a capacity of more than

Based on the above configuration, the operating principle of the storage medium is
I'll do it. After the pulse voltage is applied, a current flows in the direction of the arrow (actually radially) in the resistance layer 15 until the discharge opens, and this causes the area of the high resistance layer 120 corresponding to the lupin electrode 15 to become large. The applied voltage is divided by the threshold of the capacitor 12 and the voltage O9, 1l116 immediately below the bottle electrode 15, so that a high voltage is applied to the gap 16. On the other hand, during discharging, since the discharging time is very short, the current flowing laterally through the resistance layer 15 is small), and the capacitance during discharging becomes a series circuit of the capacitance of the dielectric layer 14 and the high resistance layer 12.

If this rounded high resistance layer 12 (D capacitance) is small, a small amount of negative charge will be generated by discharge and will adhere to the dielectric layer 14, and the potential of the dielectric layer 14 will immediately drop and the discharge will be stopped. Thereafter, a current flows in the lateral direction of the resistive layer 150, and the At/% voltage is again applied to the resistive layer 150, causing discharge to occur again.This procedure is repeated (<) to form a latent image. That is, since light is blocked by multiple medium discharges in place of one large discharge p as in the conventional case, voids in the spot can be avoided.

As described above, the present invention uses the induced current flowing through the intermediate resistance layer 1s to artificially change the capacitance between discharge and other times.

As shown in FIG. 2, a voltage VPs, for example 600 V, is applied to the threshold of the metal support 11 and the pin electrode 1i15 through a switch (SW) in the configuration shown in FIG. -Electric layer 1
40 surface When Vs on the surface and Vg are the air gap voltages, the rise of the air gap voltage is expressed by the following equation.

Round K”-1+Ce/Cp Co; Composite capacity of recording layer 1/Kt=Re(Cp-I-C@) Cp;
i1% resistance resistance capacitance/rfe; surplus function RC;
The resistance value of the resistance layer.Equation (3) is normalized by the air gap voltage OI and the final value.

Generally, the interval between the applied voltages of recording pulses is several tens of microseconds.

The resistance layer 150 * surface resistance R@ required for this purpose is approximately 10"Q/port or less (according to equation (3)). On the other hand, when determining the condition that the capacitance does not change within the ion movement time of approximately 2 ns, ( 3
) 2 Ra is approximately 10-shiro or more. This is p resistance layer 1
It can be seen that the object of the present invention can be achieved if the surface resistance cell is within the range of 10·Ω/mouth (Re(10·Ω/mouth).

The resistance value of the high resistance layer 12 is necessary to neutralize the charge on the resistance layer 13 and keep the potential of the resistance layer 15 almost constant after the pulse is applied.

The pulse voltage application period is 1 life, 400 ns, and 84 degrees.

It is considered that it is sufficient if the p time constant is 100 ns II degrees or more.

Under these conditions, the volume resistance of the p14 resistive layer 120 is approximately 10"
It becomes Ω・pieces or more. On the other hand, the upper limit is determined by the condition that there is no interference between processes. Generally speaking, it is related to the physical layout of each process, but it is sufficient to consider that it is about a1 second.

This means that pp is less than 1011Ω·1.

Based on the above, the volume resistivity β of the high resistance layer 120 is 10”Ω・
The value ρ is (10 11 Ω·1). If this condition is used, there is no mutual interference between the processes, and a good latent image can be formed.

On the other hand, if the resistance layer 12 is a perfect insulator, the resistance layer 15
If the electric current fILt flowing through is set to a uniform potential, it is necessary to flow it in a uniform direction. Therefore, as will be described later, the resistance layer 15 is placed on the high resistance layer 12 formed on the metal support 11.
If the 0 width is made larger than the width of the high resistance layer 120, and the steps are 1/sK so that both ends can be connected to the metal support 11, the dielectric layer is applied from above. This allows the resistance layer 13 to be easily grounded. With this method, there is no need for a special mechanism to ground the resistance layer, and it may be possible to select the resistance value of the resistance layer! It has the advantage of being wider.

FIG. 4 is an explanatory diagram of the configuration of Embodiment 0 of the present invention.

As shown in the figure, a volume resistivity of 3×10 is placed on the metal drum 11.
- 100μ of the resistance layer 12 of Ω・aw Oj% is applied, and a surface rH resistance of 10′Ω/LIO resistance layer 15 t 1 is applied thereon.
An electrostatic sickle medium 1 having a structure of 0 am jk cloth t and a #electric layer 14 of a material having a relative dielectric constant of 52 coated thereon to a thickness of 20 μm is prepared. As shown in FIG.
EC charges. Then, both ends of the resistance layer 150 are set to a predetermined potential value of 0 to -150V related to the discharge time.

A good S-image without p1 spots and voids was formed by applying a voltage of 9 non-contact electric bottles (5 to 150 VC) to the fresh noodles of IIk20 tug to form an electrostatic latent image. Ru.

FIG. 5 shows the configuration of another embodiment of the present invention! This is a beak diagram.

In the figure, a dielectric film is used for the high resistance layer 12, and the ends of the resistance layer 12C)j1m are connected to the metal support 11, resulting in a nine-layer configuration. The 70@0 condition is the same as the JIEJ diagram. An experiment was conducted using this recording medium 1', and it was found that there was no interaction between each process, and there was no occurrence of voids in the spot.
& A beautiful latent image was formed. In this embodiment, the metal support is a metal drum; however, it goes without saying that it may be constructed in the form of a belt and may be made of a highly conductive material.

(Effects of Phrase Example 1! As explained above, according to the present invention, there is no shortage of initial electron supply, and the current during discharge can be suppressed by the functions of the resistance layer and the high resistance layer. It is important to form a good distance without voids in the spot.

[Brief explanation of drawings]

Figure 1s1 is a general explanatory diagram of the enlarged electromagnetic recording system, Figure 2 is the basic configuration of the main parts of the present invention, and Figure 3 is an explanatory diagram of the same operation as above.
Figure 4 is an explanatory diagram of the configuration of the present @O embodiment, and Figure 5 is the present @O embodiment.
6 in the diagram to explain the configuration of another embodiment], in the figure, 1 is a rope body, 2.5 is a corona discharger, 3.15 is a bottle electrode, and 4Fi
Magnetic brush developing machine, 6 is plain paper, 11 is metal support, 1
2 shows the Am resistance layer, 15 shows the resistance layer, 14 shows the epigastric layer, and 16 shows the void. Patent Applicant: Fujitsu Ltd. Kinsha, Successor: Benshio 1) Yoshiyoshi Saka, Figure 100, Figure 2

Claims (4)

[Claims] (1) Used in an electrostatic recording device and forms a electrostatic latent image on a conductive support layer with a threshold voltage of V/electron, which can be transferred to plain paper after death. In the recording medium, the lower layer includes a high resistance layer and a resistance layer set at a predetermined potential related to the discharge time. An electrostatic recording medium further comprising a dielectric layer for forming an electrostatic image (by discharge) thereon. (2) The volume resistivity of the high resistance layer O is 101 to 1g1lΩ
Claims 1811I&1 characterized by nine countries
Electrostatic recording medium described in Section 1. (3) The electrostatic recording medium according to claim 1, wherein the resistance layer has a surface resistance of 10@6 to 10@Q/mouth. (4) # Claims characterized in that both ends of the paper distribution layer are directly connected to the conductive support! Iris 1 section Ik2
QiO electrostatic brass fabric. (The electrostatic recording medium according to claim 1, wherein the capacitance of the high resistance layer is 50 PF/- or less.