JPH04479A - Transfering and fixing device - Google Patents

Abstract

PURPOSE:To perform transfer and fixation only with pressure in a secondary transfer part, to eliminate the need of heating an intermediate transfer body, to miniaturize a device, to reduce cost, to make power consumption low and to shorten a warming-up time by using a microcapsule toner. CONSTITUTION:The microcapsule toner 34 is obtained by encapsulating fixing component 32 and a coloring material 33 into a microcapusle 31. When the outside shell of the capsule is destroyed and volatile liquid in the component 32 is exposed to air, a polymer material incorporates the material 33 to be solidified, so that the fixation is accomplished. Namely, the intermediate transfer body 16 is allowed to press-contact with a toner image 30a formed on an image carrier 1 in a conventional method to such an extent that the outside shell of the microcapsule toner is not destroyed by a roller 17, and the image is adhesively transferred. The transferred toner image 30b is allowed to strongly press-contact with a recording body 12 by the pressure roller 20 of the secondary transfer part 15 and fixed as a recorded image 30c. Since heat is not utilized, the deterioration of the performance of an image holding body and filming are prevented and the device is miniaturized.

Description

[Detailed Description of the Invention] [Summary] Regarding a transfer fixing device used in a recording device such as an electrophotographic recording method or an electrostatic recording method, it is possible to prevent performance deterioration of an image carrier and toner filming, and to improve the performance of the device. Downsizing and cost reduction.

In order to achieve low power consumption and shorten warm-up time, the toner image formed on the image carrier is adhesively transferred to the intermediate transfer body in the primary transfer section, and then the toner image on the intermediate transfer body is transferred to the intermediate transfer body. In a transfer fixing device that pressure-transfers a toner image onto a recording medium in a secondary transfer section, a microcapsule toner is used as the toner.

[Industrial application field]

The present invention relates to a transfer fixing device used in an electrophotographic recording system or an electrostatic recording system.

This type of transfer fixing device is of a type that adhesively transfers a toner image formed on an image carrier such as a photosensitive drum to an intermediate transfer member, and then fuses and transfers the toner image on the intermediate transfer member to a recording member. There is. This transfer fixing device is required to transfer and fix the toner image formed on the image carrier onto the recording medium without causing any disturbance.

[Conventional technology]

Conventionally, a toner image formed on an image carrier such as a photosensitive drum is exposed to corona discharge,
A charge is applied using a bias voltage or the like, and the image is electrostatically transferred to the recording medium.

However, the electrostatic transfer method has the disadvantage that charge disturbance occurs during transfer and dust is generated around the transferred toner image.

In view of the above drawbacks, for example, in various publications such as Japanese Patent Publication No. 46-41679, Japanese Patent Publication No. 48-22763, and Japanese Patent Publication No. 57-20632, after a toner image is transferred by being brought into pressure contact with an intermediate transfer member, A method has been proposed in which a toner image is transferred and fixed onto a recording medium. According to this method, unlike electrostatic transfer, a toner image can be transferred onto a recording medium without disturbance.

The basic configuration of a conventional recording device using an intermediate transfer body is explained in the sixth section.
As shown in the figure. In the figure, 1 is an image carrier such as a photosensitive drum, 2 is a charger, 3 is an exposure device, 4 is a developer, 5 is a cleaner, 6 is a belt-shaped intermediate transfer member, 7 is a pressure roller, and 8 is a hack-up 9 is a tension roller, 10 is a heat roller, 11 is a heater, 12 is a recording medium such as paper, 13a, 13b
is a toner image, 13c is a recorded image, 14 is a primary transfer part, 15
is the secondary transfer section. The intermediate transfer body 6 is made by forming a transfer layer on a base material by coating or the like.

As the base material, a stainless steel belt or a belt-shaped polymer resin film with excellent heat resistance such as polyimide is used. Rubber with excellent heat resistance and mold release properties, such as silicone rubber and fluororubber, is used for the transfer layer.

The operation of the recording apparatus having such a configuration is as follows.

The intermediate transfer body 6 rotates in the direction of the arrow as the backup roller 8 rotates, and the speed of the intermediate transfer body 6 is adjusted to match the peripheral speed of the image carrier 1, which rotates in the clockwise direction indicated by the arrow. ing. The surface of the image carrier 1 is first uniformly charged by the charger 2 . Next, an electrostatic latent image is formed on the surface by the exposing device 3, and the electrostatic latent image is visualized by the developing device 4 to become a toner image 13a. The toner image 13a is transferred to the intermediate transfer body 6 at the primary transfer section 14, where the intermediate transfer body 6 is pressed against the image holding body 1 by the pressure of the pressing roller rough. Toner remaining on the image carrier 1 after transfer is cleaned by a cleaner 5. The toner image 13b on the intermediate transfer body 6 is transferred to the heat roller 1 having a built-in heater 11.
0 and the hack-up roller 8 transfer and fix the image onto the recording medium 12 in the secondary transfer section 15 to form a recorded image 13c.

[Problems to be Solved by the Invention] In a transfer fixing method using an intermediate transfer member, in order to improve the transfer efficiency by enabling the transfer of toner images without disturbance, the pressure roller 7 and the image carrier 1 are opposed to each other. Pressure transfer is performed in the installed primary transfer section 14, and the heating roller 1
Thermal fixing is performed in the secondary transfer section 15 where the toner 0 and the hack up roller 8 are disposed facing each other.

However, since the intermediate transfer body is also heated during heat fixing, if heat dissipation is insufficient when returning from the secondary transfer (thermal fixation) position to the primary transfer position, the image will be retained from the intermediate transfer body at the next transfer section. There was a problem in that heat was transferred to the body and the performance of the image carrier deteriorated. In addition, since the toner image formed on the image carrier comes into contact with the high-temperature intermediate transfer member during primary transfer (pressing),
Toner softens and adheres to the image holder (filming)
There was a problem. In order to solve such problems,
Although it is conceivable to provide a cooling device for the intermediate transfer member, there are problems in that the recording device becomes larger and the cost increases. Further, the essential problem of performing heat fixing is that it significantly increases the power consumption of the recording apparatus. Furthermore, the thermal fixing method usually requires a cross-flow fan or the like to prevent the temperature inside the recording apparatus from rising, making the recording apparatus larger and more expensive. Furthermore, it takes time for the heat roller to reach a predetermined temperature, which causes a long warm-up time for the recording apparatus.

The present invention provides a transfer fixing device that can prevent performance deterioration of an image carrier and toner filming, and also achieve miniaturization, cost reduction, and power consumption of the device, and shorten warm-up time. is intended to provide.

[Means for Solving the Problem] In order to achieve the above-mentioned object, the present invention adhesively transfers a toner image formed on an image carrier with toner to an intermediate transfer member in a primary transfer section, and then transfers the toner image to the intermediate transfer member. In a transfer fixing device that pressure-transfers a toner image on a body onto a recording body in a secondary transfer section, a microcapsule toner is used as the toner.

Further, in the above transfer fixing device, a microcapsule toner consisting of a coloring material and a fixing component having a photocurable resin is used as the toner, and ultraviolet rays are irradiated to the toner image pressure-transferred onto the recording medium in the secondary transfer section. A configuration including a light source may also be used.

Furthermore, in the above transfer fixing device, a microcapsule toner comprising a coloring material and a fixing component having a photocuring resin is used as the toner, and the intermediate transfer body is formed of a transparent material, and the intermediate transfer body and A light source may be provided inside the intermediate transfer body to irradiate the toner image transferred onto the recording body with ultraviolet rays while the intermediate transfer body is in pressure contact with the recording body.

[Function] By using microcapsule toner, transfer and fixation can be performed using only pressure without using heat in the secondary transfer section, so the intermediate transfer body is not heated, and when using heat fixation, In comparison, the recording device can be made smaller, lower in cost, and lower in power consumption. Furthermore, since no heat roller is used, warm-up time can be shortened.

〔Example〕

The present invention will now be described in detail with reference to FIGS. 1-5.

A first embodiment is shown in FIGS. 1 and 2.

FIG. 1 is a side view showing the general structure of the transfer fixing device of this example, in which 16 is an intermediate transfer body, 17 is a pressure roller, 18 is a backup roller, 19 is a tension roller, 20 is a pressure roller, 21 is a bracket, 22 is a spring, 30a,
30b is a toner image. Note that the same reference numerals are used for the same parts as in the past. In FIG. 1, pressure roller 20
is in pressure contact with the intermediate transfer body 16 on the backup roller 18 through a bracket 21 and is urged by a spring 22.
The pressure contact force can be adjusted around eight times depending on the amount of displacement of the spring 22.

The intermediate transfer body 16 configured as a seamless belt is
It is formed by coating a 100 μm thick polyester film base material with 400 μm thick silicone rubber.

The toner used in this device is a microcapsule toner. This microcapsule toner 34 is a well-known toner, and as shown in FIG. 2, a fixing component 32 and a coloring material 33 are encapsulated in microcapsules 31. There are two types of such microcapsule toners; one type uses a volatile liquid as a fixing component, and the other type uses a solid solution as a fixing component. Regardless of the type, the fixing component and coloring material are still enclosed within the shell. The volatile liquid as a fixing component is a solution of a suitable polymer material dissolved in a highly volatile solvent such as alcohol, and when the outer shell of the capsule is broken and the solution is exposed to the air, ,
The highly volatile solvent evaporates rapidly, resulting in the polymeric material darkening by incorporating the colorant, thereby achieving fixation. On the other hand, the solid solution as a fixing component is
It is a gel-like body containing a polymer material with a high boiling point and a polymer material with a low boiling point, and its fixing mechanism is almost the same as when a volatile liquid is used as a fixing component. That is, when the outer shell of the capsule is destroyed, the gel-like body is exposed to the air, the polymer material with a low boiling point evaporates, and as a result, the polymer material with a high boiling point solidifies while incorporating the colorant. become. Incidentally, when the above-mentioned microcapsule toner is fixed, that is, when its outer shell is destroyed, a linear pressure of 10 to 15 kgf/cm is applied to the microcapsule toner.

Now, in the transfer fixing device of the present invention, the above-mentioned microcapsule toner is formed on the image carrier by the same developing method as conventional toner. Then, in the next transfer section 14, the toner image 30a formed on the image carrier 1 is transferred to the intermediate transfer member 16.
are brought into contact with each other by the pressure of the pressure roller 17, and the intermediate transfer body 16
The toner is adhesively transferred using the adhesive force of the silicone rubber that is the transfer layer. The pressure applied by the pressing roller 17 at this time is adjusted to a pressure that does not destroy the outer shell of the microcapsule toner, that is, a pressure lower than a linear pressure of about 10 kgf/cm, preferably about 1 kgf/cm. The toner image 30b transferred onto the intermediate transfer body 16 is subjected to pressure by a pressure roller 20 in the secondary transfer section 15. The pressure at this time is adjusted to a linear pressure of 10 to 15 kgf/cm by changing the amount of displacement of the spring 22. When the microcapsule toner 34 receives this pressure, its outer shell microcapsule 31 is destroyed and the fixing component is exposed. This fixing component is repelled by the releasability of the silicone rubber of the pressure roller 20, and at the same time is attached to the recording medium 12 by being entangled in its fibers. In this way, the toner image that has passed through the secondary transfer section becomes a recorded image 30c and is attached to the recording medium 12.

As described above, since microcapsule toner is used in this example, transfer and fixation can be performed from the intermediate transfer body to the recording body using only pressure without using heat in the secondary transfer section. This prevents the performance deterioration of the image carrier and toner filming caused by the heating of the intermediate transfer member, which has become a problem, and makes the recording device more compact than when thermal fixing is used.
Cost and power consumption can be reduced. Furthermore, since no heat roller is used, warm-up time can be shortened.

In the above description, an example in which a belt-shaped intermediate transfer member is used has been described, but a roller-shaped intermediate transfer member may also be used. In this case, there is an advantage that the intermediate transfer section can be made more compact.

A second embodiment is shown in FIGS. 3 and 4.

FIG. 3 is a side view showing the general structure of the transfer fixing device of this example. In the figure, 41 is an ultraviolet lamp equipped with a light source 42a and a reflecting plate 42b, 43a and 43b are toner images, and 43c is a recorded image.

In the previous example, a microcapsule toner that uses a volatile liquid as a fixing component or a gel-like material (
A microcapsule toner using solid solution) was used, but
These have the following drawbacks.

The advantage of the former (using a volatile liquid as the fixing component) is that the highly volatile solvent evaporates rapidly during fixing, so fixing is done quickly and stably. The disadvantage is that the highly volatile solvent gradually escapes through the outer shell of the capsule, resulting in
There has been a problem that the properties of the fixing component change and the fixing properties deteriorate. Also, the advantage of the latter is that it can be stored for a long time without deteriorating quality.
On the other hand, the drawback is that if the image area is touched with a finger after fixing, the area may peel off, and fixing cannot be performed quickly and stably.

This example solves these drawbacks by using a microcapsule toner consisting of a coloring material and a fixing component containing a photocurable resin, and using an ultraviolet lamp 41.
has been established.

The microcapsule toner used in this example is formed by the following method.

That is, first, 1 part by weight of carbon black powder as a coloring material, 40 parts by weight of photocurable resin, 19 parts by weight in total of diisocyanate and epoxy resin (in this example, 1 part by weight for 8 parts of epoxy resin) Diisocyanate 11 was used, but
(the ratio may vary somewhat) and dibutyl phthalate 4
0 parts by weight and thoroughly stirred with a ball mill to obtain mixed solution A
Adjust. Examples of photocurable resins include Yokohama Rubber Co., Ltd.
A photo-curable coating material (product number UD-246) sold by Kawasaki Co., Ltd. is used. Such a photocurable coating material has the property of being cured in a short time by irradiation with ultraviolet light of 300 to 400 nm.

In this example, the epoxy resin and the photocurable resin in the liquid mixture A serve as the fixing components. Next, a mixed liquid B consisting of polyvinyl alcohol and hexamethylene isocyanate is prepared, and while stirring this mixed liquid B, mixed liquid A is gradually added to the mixed liquid B to make the mixed liquid A into fine particles. from room temperature to 60-80°C. When this temperature state is maintained for 30 minutes to 3 hours, a hard outer shell of polyurea is formed on the surface of each fine particle of mixture A through a polymerization reaction, resulting in a particle size of 11 to 17 μm.
A microcapsule slurry is obtained.

Thereafter, nigrosine as a charge control agent and hydrophobic silica as a fluidizing agent are added to this microcapsule slurry, and the slurry is then dried with a spray dryer to obtain a powdered microcapsule toner. The structure of such a microcapsule toner is schematically shown in FIG. 4. In FIG. 4, 45 is a fixing component; 46 is a fixing component;
47 is a coloring material, that is, carbon black powder, and 47 is a polyurea capsule shell. The fixing components are an epoxy resin and a photocurable resin as described above, and dibutyl phthalate is also mixed therein. That is, the coloring material 46 of carbon black powder exists in a suspended state in the mixed liquid of epoxy resin, photocurable resin, and dibutyl phthalate. The thickness of the polyurea capsule shell 47 is 0.
It is 2 to 0.3 μm. Further, it is desirable that the viscosity of the fixing component be as low as about 10 to 10,000 cps so that the fixing component quickly permeates into the recording medium when the capsule shell is broken.

In the above description, an example has been shown in which the microcapsule toner 44 is manufactured by an interfacial polymerization method, but other methods such as a coacervation method, an in-5 in situ polymerization method, or US Pat. No. 3,338,991 are also possible.

No. 3,326,848, No. 3,502,
It is also possible to use the method disclosed in No. 582.

Furthermore, emulsion polymerization method, internal polymerization method, seed polymerization method, submerged drying method, etc. can also be employed.

Furthermore, iron powder or magnetic powder that acts as a magnetic brush during development can be mixed into the microcapsule toner as necessary.

Now, in the transfer fixing device of this example, the toner image 43a of the microcapsule toner containing the above-mentioned photocurable resin is formed on the image carrier 1 by the same developing method as the conventional one.

This toner image 43a is transferred to the -next transfer section 14 as in the previous example.
The toner image 43 is adhesively transferred to the intermediate transfer member 16 at
b, and the toner image 43b is subjected to pressure by the pressure roller 20 in the secondary transfer section 15. When the microcapsule toner receives this pressure, its outer shell is destroyed and the fixing component is exposed. This fixing component is repelled from the pressure roller 20 due to the releasability of the silicone rubber, and at the same time is attached to the recording medium 12 by being entangled within its fibers. In this way, the toner image is transferred to the recording medium 12 in the secondary transfer section 15, but at this time, the fixing component is not cured. Next, the toner image transferred to the recording medium 12 is irradiated with ultraviolet light by four ultraviolet lamps.
As a result, the fixing component quickly hardens while incorporating the coloring material, and is fixed on the recording medium 12 to form a recorded image 43c.

According to this example, the same effects as the previous example can be obtained, and the problems of the previous example are solved, so that it can withstand long-term storage without deteriorating quality, and achieves rapid and stable fixing.

FIG. 5 shows a third embodiment.

FIG. 5 is a side view showing an outline of the structure of the transfer fixing device of this example. In the figure, 51 is an intermediate transfer member, and 52 is a hack-up roller.

In this example, the intermediate transfer body 51 and the bank unroller 52
is made of a transparent material, and the ultraviolet lamp 41 is provided within the hack-up roller 52 and faces the pressure roller 20. The rest is the same as the previous example.

In the case of this example, the toner image of the microcapsule toner 44 is transferred to the intermediate transfer body 51 in the primary transfer section 14 as in the previous example. This toner image 43b is transferred onto the recording medium 12 in the secondary transfer section 15, but at the time of this transfer, the ultraviolet light emitted from the ultraviolet lamp 41 passes through the transparent backup roller 52 and the transparent intermediate transfer body 51. The toner image is irradiated with the toner image, whereby the fixing component quickly hardens while incorporating the coloring material and is fixed on the recording medium 12 to form a recorded image 43c.

In this example, the same effects as in the second example can be obtained.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to prevent performance deterioration of the image carrier and toner filming, and also achieve miniaturization, cost reduction, and power consumption of the apparatus, and shorten the warm-up time. can do. In addition, when using a microcapsule toner containing a photocurable resin,
In addition to being able to withstand long-term storage without deteriorating quality,
It becomes possible to achieve fast and stable fixing.

[Brief explanation of drawings]

FIG. 1 is a side view showing an outline of the structure of a transfer fixing device according to a first embodiment of the present invention; FIG. 2 is a structural explanatory diagram of a microcapsule toner; FIG. 3 is a second embodiment of the present invention. FIG. 4 is an explanatory diagram of the structure of the microcapsule toner. FIG. 5 is a side view showing the structure of the transfer fixing device according to the third embodiment of the present invention. 6 is a basic configuration diagram of a conventional recording device using an intermediate transfer body, in which 1 is an image holding body, 12 is a recording body, 14 is a primary transfer section, 15 is a secondary transfer section, 16.51 32.45 is a fixing component; 33.46 is a coloring material; and 34.44 is a microcapsule toner 42a as a light source. FIG. 1 is a side view showing an outline of the structure of a transfer fixing device according to a first embodiment of the present invention.

Claims (1)

[Claims] 1. After the toner image formed with toner on the image carrier (1) is adhesively transferred to the intermediate transfer body (16) in the primary transfer section (14), the toner image is transferred onto the intermediate transfer body (16). What is claimed is: 1. A transfer and fixing device for pressure-transferring a toner image onto a recording medium in a secondary transfer section (15), characterized in that a microcapsule toner (34) is used as the toner. 2. The toner image formed with toner on the image carrier (1) is transferred to the primary transfer section (14)
A transfer and fixing device that adhesively transfers the toner image on the intermediate transfer body (16) in the intermediate transfer body (16) and transfers the toner image on the intermediate transfer body (16) under pressure to a recording body in the secondary transfer unit (15), and a fixing component having a photocurable resin, and a light source (42a) that irradiates the toner image pressure-transferred onto the recording medium in the secondary transfer section (15) with ultraviolet rays. A transfer fixing device characterized by being provided with a transfer fixing device. 3. After the toner image formed on the image carrier (1) is adhesively transferred to the intermediate transfer body (51) in the primary transfer section (14), the toner image on the intermediate transfer body (51) is transferred to the secondary transfer body (51). In a transfer fixing device that performs pressure transfer onto a recording medium in a transfer section (15), a microcapsule toner (44) comprising a coloring material and a fixing component having a photocurable resin is used as the toner, and the intermediate transfer body (51) is made of a transparent material, and
A light source (42a) is provided inside the intermediate transfer body (51) for irradiating the toner image transferred onto the recording body with ultraviolet rays while the intermediate transfer body (51) and the recording body are in pressure contact with each other. A transfer fixing device characterized by: