JPH02162379A - Intermediate image carrier and image forming device having same - Google Patents

Abstract

PURPOSE:To prevent oil from oozing out of a heat resistant elastic layer and to improve picture quality by constituting an intermediate image carrier by forming the heat resistant elastic material layer and fluorine-containing resin layer on a base roller having a heat source. CONSTITUTION:The intermediate image carrier 1 is equipped with the heat resistant elastic layer 12 and fluorine-containing resin layer 13 provided on an indication roller 11 having an infrared-part lamp 10 internally. Consequently, the layer 13 suppresses the oozing of oil from the layer 12, so the sticking force of the carrier 1 to toner increases to transfer a toner image smoothly from an intermediate elastic roller contacting the carrier 1, decrease the sticking amount of oil on a photosensitive drum, and prevent the sensitivity of the photosensitive drum from decreasing. Therefore, there is no toner contamination and a toner image is formed with high accuracy and high sensitivity.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention is provided in contact with a rotating body such as an electrostatic latent image bearing member having a toner image or an intermediate elastic roller, and the toner image is transferred from the rotating body. It relates to an intermediate image carrier that receives the transfer of the toner image and retransfers the toner image to paper or the like, and in particular, an intermediate image carrier that can smoothly receive the toner image transfer from the rotating body and does not cause toner contamination. The present invention also relates to an improvement in an image forming apparatus having this intermediate image carrier.

[Prior Art] As an apparatus incorporating this type of intermediate image carrier, for example, an image forming apparatus using conductive toner as a developer is known.

That is, in this image forming apparatus, since the toner image cannot be transferred from the latent image carrier to the paper side by the transfer corotron, the intermediate image carrier is incorporated, as shown in FIG. A photosensitive drum (a) on which a toner image is formed, an intermediate elastic roller (b) that is placed in contact with the photosensitive drum (a) and has a heat-resistant elastic layer (bl) on its outer peripheral surface, and this intermediate elastic roller (b). ), has a heating source (C1) inside, and has a heat-resistant elastic layer (C1) on the outer peripheral surface.
2) and a pressure roller (d) disposed in contact with the intermediate image carrier (C), the main part of which is formed on the photosensitive drum (a). The toner image transferred to the intermediate elastic roller (b) is once adhesively transferred to the outer peripheral surface of the intermediate elastic roller (b), and the toner image transferred to the intermediate elastic roller (b) is heated and melted and transferred to the intermediate image carrier (C) side. The toner image was retransferred onto a sheet of paper (e) inserted between an intermediate image carrier (C) and a pressure roller (d), and fixed to form a permanent image.

[Problems to be Solved by the Invention] By the way, the conventional intermediate image carrier (C) has a metal core (C3) having a heating lamp (C1) inside, as shown in FIGS. 6 and 7. The main part thereof was composed of a heat-resistant elastic layer (C2) provided on the outer peripheral surface of the core (C3) and made of an elastic material such as silicone rubber.

Therefore, the intermediate elastic roller (b) is composed of a metal core (b2) and a heat-resistant elastic layer (bl) such as silicone rubber.
) and this intermediate image carrier (C), the heat-resistant elastic layer (C2) (bl
) have the same or similar structure, the adhesion forces to the toner are similar to each other, and the toner cannot be smoothly heated and melted and transferred from the intermediate elastic roller (b) to the intermediate image carrier (C), resulting in poor toner image quality. There were problems such as thinning of the material and parts of it being chipped.

Further, the heat-resistant elastic layer (C2) in the intermediate image carrier (C)
) has viscoelasticity, so toner and paper dust tend to adhere to its surface, but when removing toner and paper dust during cleaning operations, cleaning is difficult due to the viscoelasticity of the heat-resistant elastic layer (C2). There is a drawback that the operation is difficult and toner etc. are difficult to remove, and there is a problem that the accumulated toner is re-transferred onto the paper (e) and contaminates the toner image quality.

Further, since the oil component in the heat-resistant elastic layer (C2) easily leaks out to the outer peripheral surface and adheres to the photosensitive drum (a) via the intermediate elastic roller (b), the oil component in the oil-attached area of the photosensitive drum (a) ) has the problem that the sensitivity of the heat-resistant elastic body If
(C2) The oil component in the intermediate image carrier (C2) decreases due to leaching, and furthermore, as toner and the like accumulate on the outer peripheral surface, the releasability of the intermediate image carrier (C2) deteriorates significantly.
There was a problem that it became unusable.

Note that these problems occur not only when the intermediate image carrier (C) is placed in contact with the intermediate elastic roller (b), but also when the intermediate image carrier (C) is placed in contact with the photosensitive drum (a> Naturally, this also occurs when the surface is placed in direct contact with the surface.

[Means for Solving the Problems] The present invention has been made in view of the above-mentioned problems, and its object is to smoothly transfer a toner image from a rotating body such as an intermediate elastic roller; Moreover, it is an object of the present invention to provide an intermediate image carrier that does not cause toner contamination, and an image forming apparatus having this intermediate image carrier.

That is, the first invention is based on an intermediate image carrier that is provided in contact with a rotating body having a toner image, receives the toner image from the rotating body, and retransfers the toner image to a transfer sheet. , the intermediate image carrier includes: a support roller having a heating source inside; a heat-resistant elastic layer 7j provided on the support roller; and a fluorine-containing resin layer provided on the heat-resistant elastic layer. On the other hand, the second invention is characterized in that: an electrostatic latent image carrier on which an electrostatic latent image is formed; an intermediate elastic roller having a heat-resistant elastic layer; a support roller provided in contact with the intermediate elastic roller and having a heating source inside; a heat-resistant elastic layer provided on the support roller; and the heat-resistant elastic body. An intermediate image carrier comprising a fluorine-containing resin layer provided on a layer, and a pressure roller disposed in pressure contact with the intermediate image carrier, and is capable of handling an electrostatic latent image on the electrostatic latent image carrier. The toner image is sequentially transferred from this electrostatic latent image carrier to an intermediate elastic roller and an intermediate image carrier, and the toner image transferred to the intermediate image carrier is transferred to a sheet that is inserted between the intermediate image carrier and the pressure roller. It is characterized by being transferred to a transfer sheet and fixed.

In such technical means, the support roller that constitutes a part of the intermediate image carrier needs to have high heat conductivity and rigidity that can transfer thermal energy from an internal heating source to the heat-resistant elastic layer. , specifically stainless steel alloys, aluminum,
This can be constructed from metal materials such as iron and copper.

In addition, the heat-resistant elastic layer provided on the support roller has an elastic force and thickness that can contact the rotating body on which the toner image is formed with an appropriate pressing force and contact width, and a fluorine-containing layer that absorbs the thermal energy from the heating source. High heat conductivity is required to enable heat transfer to the resin layer, specifically elastomers with metal-containing fillers dispersed therein, such as fluorosilicone elastomers, silicone carbonate elastomers, various other silicone rubbers, fluoroelastomers such as fluororubbers, etc. , vinylidene fluoride-based elastomers, various organic rubbers such as ethylene/propylene diene rubber, various copolymers, and the like.

In addition, the thickness dimension of this heat-resistant elastic layer is set to about 0.2 to 4 m+ in consideration of the above, and on the other hand, the thermal conductivity λkj
Irhao, 5xio-” ~2.5X10-3Cat/
Set to about cm-sec-deg. in this case,
The metal-containing filler that adjusts the thermal conductivity λ to an appropriate value includes copper, tin, silver, zinc, aluminum, iron, lead, molybdenum, platinum, gold, beryllium, nickel, chromium, iridium, ruthenium, tungsten, Metals such as cadmium and vanadium, alloys of these metals, oxides of these metals, and salts of these metals can be used.

On the other hand, the fluorine-containing resin layer provided on the heat-resistant elastic layer is made of tetrafluoroethylene perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene (TFE), tetrafluoroethylene-hexafluoropropylene copolymer, This can be configured by combining (FEP) or the like.

In this case, it is desirable to set the thickness of the fluororesin layer to such an extent that the elastic deformation of the lower heat-resistant elastic layer is not suppressed, and specifically, it is preferably set in the range of 1 to 50 μm. Good. Also, as a method for forming this fluororesin layer, a support roller is set in a heat-shrinkable tube made of fluororesin, and the metal-containing filler is dispersed between the support roller and the heat-shrinkable tube. A method of injecting an elastomer and vulcanization molding, or a method of applying a liquid mixture of a fluorine-containing resin and an appropriate adhesive onto a heat-resistant elastic layer provided on a support roller, and drying it by heating. etc. are available.

Although it is not clear why the adhesion of this intermediate image carrier to toner is improved by providing a fluorine-containing resin layer on the heat-resistant elastic layer, the reason why the fluorine-containing resin layer improves the adhesion of the toner to the heat-resistant elastic layer is that the fluorine-containing resin layer improves the elastic deformation of the heat-resistant elastic layer. This is believed to be because the leaching of oil, which reduces toner adhesion from this heat-resistant elastic layer, is prevented without suppressing the toner adhesion. On the other hand, the reason why the toner image attached to the intermediate image carrier is transferred to the transfer sheet such as paper is that it receives thermal energy from a heat source (
The puttoner image melts and adheres to paper etc. with high surface energy.
This seems to be for penetration.

Further, this intermediate image bearing member is placed in contact with a rotating body having a toner image, and this rotating body includes an electrostatic latent image bearing member and an intermediate elastic roller placed in contact with this electrostatic latent image bearing member. etc. As the electrostatic latent image carrier, there are photosensitive drums and photosensitive belts that are equipped with a photoconductive layer and on which an electrostatic latent image is formed by image exposure processing, and there are also photosensitive drums and photosensitive belts that are equipped with a dielectric layer and that generate electrostatic latent images using an ion printing method. There are image carriers and the like on which latent images are formed. On the other hand, the intermediate elastic roller includes a support roller and a heat-resistant elastic layer provided on the support roller and made of the same material as the heat-resistant elastic layer of the intermediate image carrier.

Note that if a configuration is adopted in which an intermediate elastic roller is interposed between the electrostatic latent image carrier and the intermediate image carrier, thermal energy from the intermediate image carrier becomes difficult to be transmitted to the electrostatic latent image carrier. ,
In electrostatic latent image carriers such as photosensitive drums, there is an advantage that photosensitive deterioration does not occur. In addition, the intermediate elastic roller is 1
However, the present invention is not limited to this, and a configuration in which a plurality of them are installed may be adopted. However, it is necessary to select an appropriate material that allows toner transfer between each intermediate elastic roller.

Further, the scope of application of image forming apparatuses having intermediate image carriers includes color copying apparatuses that use insulating toner in addition to models that use conductive toner as a developer.

[Operation] According to the technical means described above, the intermediate image carrier has a support roller having a heating source inside, a heat-resistant elastic layer provided on the support roller, and a heat-resistant elastic layer provided on the heat-resistant elastic layer. This fluorine-containing resin layer prevents oil from seeping out from the heat-resistant elastic layer, so the adhesion of the intermediate image carrier to the toner increases and the intermediate The toner image is smoothly transferred from the rotating body that comes into contact with the image carrier, and the cleaning operation of the intermediate image carrier is facilitated, making it possible to prevent toner from accumulating on the intermediate image carrier. becomes.

[Examples] Hereinafter, examples of the present invention will be described in detail.
As shown in FIGS. 2 to 2, the intermediate image carrier (1) according to this embodiment is equipped with a 600W infrared lamp (10) inside, and is equipped with an aluminum support roller having an outer diameter of 48 mm and a length of 380 #. (11) is laminated on the outer circumferential surface of this support roller (11) with an appropriate primer interposed therebetween, and its thermal conductivity λ is 1.
Ox 1o-3cat / (:tx ・Sec-d
eg, H with a rubber hardness of 456 and a thickness of 2.0
TV silicone rubber (formerly GH Temperature)
Vulcanization 5ilicone Ru
A heat-resistant elastic layer (12) formed of a heat-resistant elastic layer (12) formed of
is 0.5x 1O-3cal/cIll-5eC-de
g, and a fluororesin layer (13) made of fluororesin (PFA heat shrinkable tube) having a thickness of 35 μm, and is used by being incorporated into an image forming apparatus as shown in FIG.

That is, an image forming apparatus incorporating this intermediate image carrier (1) includes a photosensitive drum (2) whose external surface is coated with a photoconductive layer, and an intermediate elastic roller disposed in contact with the photosensitive drum (2). (3), an intermediate image carrier (1) provided in contact with this intermediate elastic roller (3), and a pressure roller (4) provided in contact with this intermediate image carrier (1). This is what the main parts are composed of.

First, the photosensitive drum (2) is arranged so as to be rotatable in the direction of the arrow, and an electrostatic latent image forming section (2) is disposed along the outer peripheral surface of the photosensitive drum (2).
0), L-ner image part (21), static eliminator (22),
A cleaning section (23) and the like are arranged.

On the other hand, the intermediate elastic roller (3) and the pressure roller (4)
) are rotatably arranged aluminum support rollers (30) (40), and this support roller (30).
The heat-resistant elastic body 1m (31>(41)) is provided on the outer peripheral surface of (40) and made of HTV silicone rubber.

In the image forming apparatus configured in this way, an electrostatic latent image forming portion (
At 20), an electrostatic latent image is formed which is developed into a visible image by a conductive component toner at a toner development station (21), and this toner image is brought into contact with an intermediate elastic roller (3). delivered to the contact site.

At this contact portion, the toner image is formed on the photosensitive drum (2).
Since the adhesive force to the intermediate elastic roller (3>) is stronger than the electrostatic attraction force to the intermediate elastic roller (3), the toner image on the photosensitive drum (2) is adhesively transferred to the intermediate elastic roller (3).

Next, the toner image transferred to the intermediate elastic roller (3) side is conveyed to the contact area with the intermediate image carrier (1) as the intermediate elastic roller (3) rotates. Since the adhesion force of the toner image to the intermediate image carrier (1) is stronger than the adhesion force of the toner image to the intermediate elastic roller (3) at the portion, the toner image on the intermediate elastic roller (3) is attached to the intermediate image carrier ( 1) Transferred by heating and melting to the side.

As the intermediate image carrier (1) rotates, the toner image transferred to the intermediate image carrier (1) is transported to a contact area with the pressure roller (4), and on the way, the toner image is The intermediate image carrier (10) completely melts when supplied with thermal energy from the lamp (10) and becomes releasable.
) and the pressure roller (4>) and is then retransferred to the paper (5) side that is inserted between them and fixed to become a permanent image.

Note that the photoconductive layer of the photosensitive drum (2) to which the toner image has been transferred has its photoconductive layer neutralized in a static eliminating section (22), and cleaned in a cleaning section (23) before being used for the next process.

At this time, in this image forming apparatus, an intermediate image carrier (1) incorporated in this apparatus has an infrared lamp (10
) with a support roller (11>);
1) A heat-resistant elastic layer (12) provided on the heat-resistant elastic layer (12) and a fluorine-containing resin layer (13) provided on the heat-resistant elastic layer (12).
), and since this fluororesin layer (13) suppresses oil leaching from the heat-resistant elastic layer (12), the adhesion force of the intermediate image carrier (1) to the toner increases and this intermediate image carrier (1) Intermediate elastic roller (3) in contact with image carrier (1)
In addition to smoothing the transfer of the toner image from the photosensitive drum (2), the amount of oil adhering to the photosensitive drum (2) is reduced.
It is also possible to prevent sensitivity deterioration.

Therefore, it has the advantage that a high-density toner image can be formed with high accuracy on the paper (5) pushed between the intermediate image carrier (1) and the pressure roller (4) without causing image defects or the like. are doing.

Furthermore, the heat-resistant elastic layer (12) is difficult to clean.
Since the fluorine-containing resin layer (13) is provided on the outer peripheral surface of the
The cleaning operation of the intermediate image carrier (1) becomes easier, and toner etc. do not accumulate on the outer peripheral surface of the intermediate image carrier (1).
5) It has the advantage of preventing toner contamination and greatly improving the life of the intermediate image carrier (1).

(Comparative Example) ◎First Comparative Example The above intermediate image carrier was equipped with a 600W infrared lamp inside, an aluminum support roller with an outer diameter of 48NRφ and a length of 380IIun, and a primer was appropriately applied to the outer peripheral surface of the support roller. The thermal conductivity λ is 1. Ox 1
O-3cal/ctB-sec-deg,-f
HTV with a hardness of 45° and a thickness of 2.0#I#l
This embodiment is different from the above embodiment except that it is composed of a heat-resistant elastic layer made of silicone rubber.

Table 1 shows the test results of toner transfer performance, cleaning performance, and life expectancy of this intermediate image carrier incorporated into an image forming apparatus similar to that of the example.

◎Second Comparative Example The above intermediate image carrier was equipped with a 600W infrared lamp inside, and was laminated with an aluminum support roller having an outer diameter of 48#1IIIφ and a length of 380M, and an appropriate primer interposed on the outer peripheral surface of the support roller. , whose thermal conductivity λ is 0.5xlO
3cat 7cm-sec-deg, thickness 35
This embodiment is different from the above embodiment except that it is composed of a fluororesin layer made of micrometer fluororesin (PFA heat shrinkable tube).

Table 1 shows the test results of toner transfer performance, cleaning performance, and life expectancy of this intermediate image carrier incorporated into an image forming apparatus similar to that of the example.

However, the toner transferability test of the intermediate image bearing member refers to the transferability from the intermediate elastic roller to the intermediate image bearing member. Δ: 0 indicates that almost no residue remains.

In addition, the cleaning property test of the intermediate image carrier means whether or not cleaning is possible when cleaning the outer peripheral surface of the intermediate image carrier with a blade type cleaner. is indicated by a circle.

Furthermore, the lifespan test of the intermediate image carrier means that when the intermediate image carrier is incorporated into an image forming apparatus and used continuously, the toner transfer from the intermediate elastic roller to the intermediate image carrier and the intermediate image This refers to a test for a period during which toner retransfer from the carrier to the paper can be reliably performed.
．． The case where 000 sheets can be used is indicated by ◯, and the case where less than this is usable is indicated by ×.

As is clear from these results, although the intermediate image bearing member according to the first comparative example is slightly capable of toner transfer from the intermediate elastic roller, its cleaning performance and lifespan are extremely poor, making it unsuitable. Ta.

On the other hand, the intermediate image bearing member according to the second comparative example had extremely poor toner transfer properties, although it had good cleaning properties and longevity, and was not suitable as in the first comparative example. .

In addition, FIG. 4 shows the set temperature and the toner intermediate image carrier at each set temperature (■...First Comparative Example, ■...Second Comparative Example, and ■...Relating to Examples) FIG. 3 is a graph showing the relationship between the adhesion force and the adhesion force of the toner to the intermediate image bearing member according to the example.

However, the toner adhesion force means the adhesion force of the toner formed on each intermediate image bearing member to these intermediate image bearing members, and specifically, the toner formed on the surface of each intermediate image bearing member is
It is expressed as the force (g) when the toner is transferred onto a sheet of paper having a width of m, and the sheet, on which the toner is entirely covered, is peeled off from each intermediate image carrier.

[Effects of the Invention] As described above, the present invention provides an intermediate image carrier having a support roller having a heating source inside, a heat-resistant elastic layer provided on the support roller, and a heat-resistant elastic layer provided on the heat-resistant elastic layer. This fluorine-containing resin layer prevents oil from seeping out from the heat-resistant elastic layer, so the adhesion of the intermediate image carrier to the toner increases and the intermediate image The toner image is smoothly transferred from the rotating body that comes into contact with the carrier, and the cleaning operation of the intermediate image carrier is facilitated, thereby making it possible to prevent toner from accumulating on the intermediate image carrier. Become.

Therefore, it has the effect of forming toner images with high precision and high density on the transfer sheet without causing toner contamination, and the degree of surface deterioration is small and good even after long-term use. Since it is possible to maintain good toner releasability, it has the effect of greatly improving the life of the intermediate image carrier.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention, FIG. 1 is a perspective view of an intermediate image carrier according to this embodiment, FIG. 2 is a sectional view thereof, and FIG. FIG. 4 shows a schematic configuration diagram of an image forming apparatus in which a carrier is incorporated, and FIG. 4 shows a set temperature and an intermediate image carrier according to a first comparative example, a second comparative example, and an example of toner at each set temperature. FIG. 5 is a schematic diagram of the configuration of a conventional image forming apparatus, FIG. 6 is a perspective view of an intermediate image carrier incorporated in this apparatus, and FIG. These sectional views are shown respectively. [Description of symbols] (1)...Intermediate image carrier (2...Photosensitive drum (3...Intermediate elastic roller) (4...Pressure roller (5...Paper) (10...Infrared lamp (11...Support roller (12...Heat-resistant elastic material layer (13...Fluorine-containing resin layer) Applicant: Fuji Xerox Co., Ltd. Patent attorney: Tomohiro Nakamura (3 others) Fig.

Claims (2)

[Claims] (1) An intermediate image carrier that is provided in contact with a rotating body having a toner image, receives the toner image from the rotating body, and retransfers the toner image to a transfer sheet, the intermediate image carrier is characterized by comprising: a support roller having a heating source inside; a heat-resistant elastic layer provided on the support roller; and a fluorine-containing resin layer provided on the heat-resistant elastic layer. intermediate image carrier. (2) an electrostatic latent image carrier on which an electrostatic latent image is formed; an intermediate elastic roller disposed in contact with the electrostatic latent image carrier and having a heat-resistant elastic layer on its outer peripheral surface; An intermediate image carrier comprising a support roller provided in contact with each other and having a heating source inside, a heat-resistant elastic layer provided on the support roller, and a fluorine-containing resin layer provided on the heat-resistant elastic layer. and a pressure roller disposed in pressure contact with the intermediate image carrier, the toner image corresponding to the electrostatic latent image on the electrostatic latent image carrier is transferred from the electrostatic latent image carrier to the intermediate elastic roller and the intermediate image carrier. An image characterized in that the toner image is sequentially transferred to an image carrier, and the toner image transferred to the intermediate image carrier is transferred to a transfer sheet inserted between the intermediate image carrier and a pressure roller, and fixed. Forming device.