JP2617858B2 - Elastic body, elastic roller and fixing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elastic body formed of an addition type silicone rubber elastic material, that is, a fixing roller which is required to have releasability used in an image forming apparatus such as an electrophotographic copying machine or an electrophotographic printer. And an elastic body to be used as rollers such as a transport roller or blades such as a cleaning blade and a developing blade.
Further, the present invention relates to an elastic roller using the above-mentioned elastic body and a fixing device having the elastic roller.

[0002]

2. Description of the Related Art A pair of elastic rollers used for an image forming apparatus such as an electrophotographic copying machine or an electrophotographic printer, which conveys a sheet recording material such as plain paper or OHP film or a transfer material along a predetermined path. In general, a transporting roller having the properties described above is required to have transportability, releasability and durability.

[0003] Blades such as a cleaning blade for removing toner and dust adhering to the surface of a photoreceptor and a developing blade for forming a thin layer of toner on a developing sleeve used in an image forming apparatus. Is functionally
It is arranged so as to slide while being in pressure contact with the toner, and requires high releasability, abrasion resistance and durability.

Among the transport rollers used in the image forming apparatus and having a pair of elastic rollers for transporting the unfixed toner image on the recording material, the fixing roller is particularly the fixing roller. The recording material must be conveyed along a predetermined path while applying pressure and heating as necessary to fix the toner image on the recording material and prevent the offset phenomenon. Wearability and durability are required.

Conventionally, in the fixing roller, a coating layer made of a material having a good releasability such as a fluorine resin or a silicone rubber is formed on a metal cored bar. In an image forming apparatus, from the viewpoint of emphasizing image quality, the fixing roller of the fixing rollers is more disadvantageous than the fixing roller coated with a fluorocarbon resin in releasing property and durability, but is made of silicone rubber having excellent image quality. There is a tendency to employ coated fixing rollers, and various researches and developments have been made on silicone rubber materials to improve the releasability and durability as much as possible.

In color electrophotography, in order to reproduce a color close to that of an original document, a plurality of toner layers are heated and melted to mix colors, so that a toner having a low softening point must be used. When a toner having a low softening point is used, when the toner is heated and fixed with a fixing roller coated with a fluorine-based resin such as Teflon used in an ordinary black-and-white copying machine, the offset phenomenon in which the toner adheres to the roller side is remarkable. And it is extremely difficult to obtain a good fixed image. In order to avoid such offset phenomenon, it is practical to apply silicone oil as a toner release oil to the fixing roller surface, which is coated with a special grade silicone rubber material with excellent release properties. It has become.

[0007]

However, the existing silicone rubber materials have insufficient releasability, and research and development have been conducted to improve the releasability and durability of silicone rubber materials as much as possible. Is as described above.

For example, according to Japanese Patent Application Laid-Open No. 61-144675, in addition-type silicone rubber, a cured product comprising a linear dimethylpolysiloxane having a molecular weight of 20,000 to 200,000 and having a terminal vinyl group blocked, has a good release. It is disclosed that it exhibits typology.

According to the above-mentioned publication, it is stated that the linear dimethylpolysiloxane having a vinyl group blocked at both ends is improved in releasability as the molecular weight increases.
However, those having a molecular weight exceeding 200,000 cause a problem in physical strength and are not considered to be practical.

Here, the relationship between the molecular weight and the viscosity of the linear dimethylpolysiloxane will be briefly described. In general, as the molecular weight of dimethylpolysiloxane increases, its viscosity also increases, and in the case of linear dimethylpolysiloxane, a molecular weight of 200,000 substantially corresponds to a viscosity of 60,000 poise.

On the other hand, in the conventional roller outer layer material composition,
When a roller coated with a release agent is used for fixing under the condition of being heated to a high temperature, a phenomenon occurs in which the release agent invades the inside of the outer layer of the roller and deteriorates the silicone rubber of the outer layer. This deterioration is particularly likely to occur inside the outer layer of the higher temperature roller.

Therefore, Japanese Patent Publication No. 54-41330 proposes to provide an oil barrier layer such as fluororubber in the intermediate layer of the silicone rubber layer of the roller outer layer.
Further JP-B 5 4- forty-one thousand three hundred and thirty-two JP, Sho 57-46
Japanese Patent Application Laid-Open No. 068 proposes that the lower layer is formed by mixing a rubber which does not easily swell. However, when the deterioration of the silicone rubber layer is prevented by the above method, it is necessary to select a material having a better releasability as the outer layer material of the roller. Therefore, at least two or more layers are formed as the outer layer of the roller. Requires configuration.

As still another method, Japanese Patent Publication No. 54-263 is known.
No. 73 proposes that the type of silicone rubber constituting the rubber layer of the roller outer layer and the type of silicone oil applied thereto are selected and combined so that the rubber layer does not swell.

However, the above-mentioned Japanese Patent Publication No. 54-2637.
No. 3 proposes that a combination of an addition type silicone rubber and phenylmethyl silicone oil is not preferable because lubrication occurs in the rubber.

Further, Japanese Patent Application Laid-Open No. 3-33786 describes a heat fixing roller having a silicone rubber elastic layer, a fluorine rubber oil barrier layer and a release silicone rubber release layer on a metal core member. The heat fixing roller is
An oil barrier layer made of fluoro rubber prevents the release agent from penetrating into the rubber elastic layer, and the release agent improves the releasability from toner, silicone oil affinity, surface smoothness, and abrasion resistance on the roller surface. Is described.

However, the release layer formed on the surface of the heat fixing roller described in JP-A-3-33786 has two or more vinyl groups in one molecule and has a polymerization degree of 5, Methyl vinyl polysiloxane containing triorganosyl hemioxane units (M units) and silicate units (Q units) in a specific ratio with respect to 100 parts by weight of 2,000 to 12,000 methyl vinyl polysiloxane (component (a)). A release layer cured using 1 to 100 parts by weight of siloxane (component (b)).

More specifically, in the examples of the specification, a release layer formed by using 30 parts by weight of the component (b) having M units and Q units with respect to 100 parts by weight of the component (a) In view of the fact that the heat-fixing roller having the above has a durable offset life of 30,000 sheets, the methyl vinyl polysiloxane of the component (b) is a polymer mainly composed of a resin segment consisting of M units and Q units. It seems to be.

Therefore, the methyl vinyl polysiloxane of the component (b) intended in this publication is mainly composed of a resin segment composed of M units and Q units, and a soft segment composed of continuous diorganosiloxane units (D units). Has a hard resin skeleton structure containing only a few tens of repeating units at most.

The release layer cured by using the methylvinylpolysiloxane of the component (b) and the methylvinylpolysiloxane of the component (a) has a poor releasability of the component (b). There is a limit to extending the life. (B)
When the mixing ratio of the components is high, there is a problem that the elastic body obtained by heat curing becomes hard and brittle.

An object of the present invention is to provide an elastic body, an elastic roller and a fixing device which solve the above problems.

That is, one object of the present invention is to provide an elastic body having excellent releasability and physical strength.

Another object of the present invention is to provide an elastic roller which is excellent in offset resistance, is capable of satisfactorily fixing an unfixed toner image on a recording material, and does not stain an image. To provide a fixing device having the same.

Still another object of the present invention is to provide an elastic roller and a fixing device which have excellent offset resistance and excellent durability and can stably fix a toner image on a recording material. That is.

[0024]

The above objects are achieved by the present invention. In summary, the present invention relates to an elastic body formed of an addition type silicone rubber elastic material,
The addition type silicone rubber elastic material, possess (a) a viscosity at 25 ° C. 80,000 poise or more terminal vinyl groups at linear dimethylpolysiloxane, and (b) a vinyl group with two or more tetrafunctional Resin segment containing at least one of
Straight chain having at least 100 or more constituent units in succession
Block- shaped oily segment with the same molecule in the same molecule
An elastic body comprising a cured product of a polysiloxane mixture having at least a resin-like organopolysiloxane having a viscosity of 10 poise or more at 25 ° C. and having a polymer .

According to another aspect of the present invention, there is provided an elastic roller for fixing an unfixed toner image carried on a recording material to the recording material, wherein the elastic roller comprises a core member and a surface of the core member. And an elastic layer formed of an addition-type silicone rubber elastic material on the side thereof. The addition-type silicone rubber elastic material includes: (a) a linear chain having a terminal vinyl group-blocking having a viscosity at 25 ° C. of 80,000 poise or more. Jo dimethylpolysiloxane, and (b) a vinyl group possess two or more, the resin segments and a bifunctional includes at least one of tetrafunctional or trifunctional
Straight chain having at least 100 continuous structural units
Block copolymers with Jo of the oil segment in the same molecule
An elastic roller comprising a cured product of a polysiloxane mixture having at least a resin-like organopolysiloxane having a viscosity of 10 poise or more at 25 ° C. having a polymer.

According to still another aspect of the present invention, there is provided a fixing device for fixing an unfixed toner image carried on a recording material to the recording material by heating and pressurizing the toner image. Heating means for holding and holding the recording material carrying the attached toner image, and having a heating means in at least one of the insides, which are in contact with each other and are rotatable in contact with the unfixed toner image, respectively. And a fixing unit having a pair of rollers including a fixing roller and a pressure roller on the side contacting the side and the opposite side, and the fixing roller includes:
It has a core member and an elastic layer formed of an addition type silicone rubber elastic material on the surface side of the core member. The addition type silicone rubber elastic material has the following properties: (a) a viscosity at 25 ° C. of 80,000 poise or more; of terminal vinyl group-blocked linear dimethylpolysiloxane, and (b) a vinyl group possess two or more, the resin segments and a bifunctional includes at least one of tetrafunctional or trifunctional
Straight chain having at least 100 continuous structural units
Block copolymers with Jo of the oil segment in the same molecule
A fixing device comprising a cured product of a polysiloxane mixture having at least a resin-like organopolysiloxane having a viscosity of 10 poise or more at 25 ° C. having a polymer .

[0027]

The present inventors have conducted intensive studies and as a result, although it is expected that the conventionally known improvement of releasability is expected, it has not been put into practical use as an elastic body in terms of physical strength. A linear dimethylpolysiloxane having a viscosity of 80,000 poise or more (corresponding to a molecular weight of 210,000 or more) having a terminal vinyl group blocked, having two or more vinyl groups, and having at least one of a tetrafunctional or trifunctional structural unit. Having a viscosity at 25 ° C. of 10 and a resin segment containing
By mixing with a range-like organopolysiloxane having a poise or more, it was made practical as an addition type silicone rubber elastic body due to the reinforcing effect of the resin-like organopolysiloxane.

Further, it has been found that the effect of improving the releasability of a linear dimethylpolysiloxane having a viscosity of 80,000 poise or more and having a terminal vinyl group blocked is more than expected from the conventional knowledge. This makes it possible to obtain an addition type silicone rubber elastic body having a good balance.

According to a study conducted by the present inventors, as an addition type silicone rubber, a linear vinyl dimethylpolysiloxane having a terminal vinyl group blocked with a viscosity of 80,000 poise or more, and a constitutional unit having tetrafunctionality or trifunctionality. Having at least a resin segment having a vinyl group-containing resin-like organopolysiloxane which is a block polymer having a resin segment having a bifunctional oil segment in the same molecule, and a specific addition type silicone rubber obtained by curing a polysiloxane mixture. It has been found that when used and combined with phenylmethyl silicone oil, it has an effect of suppressing swelling of rubber, and the above-mentioned specific addition type silicone rubber is suitable as an outer layer material of a roller.

Therefore, when an elastic layer is formed on the outer layer of the fixing roller and the pressure roller, which are a pair of rollers of the fixing device, using the elastic body of the present invention, at least one of the fixing roller and the pressure roller is formed. Swelling due to the applied silicone oil as a release agent can be suppressed, and it is not necessary to provide the roller with an oil barrier layer formed of a fluororesin.

The addition type silicone rubber elastic body of the present invention is
It is obtained by curing a mixture basically containing the following components.

Component (1): the general formula is (CH ₃ ) ₂ SiO
A linear dimethyl having a viscosity of 80,000 poise or more at 25 ° C., in which both ends comprising a structural unit represented by (bifunctional) are blocked with structural units (CH ₂ ＣＨCH) (CH ₃ ) ₂ SiO _1/2. Polysiloxane.

Component (2): a resin segment having a structural unit represented by the general formula of SiO ₂ (tetrafunctional), CH ₃ SiO _3/2 (trifunctional), and (CH ₃ ) ₂ SiO
A block polymer having an oil segment having at least 100 structural units represented by (bifunctionality) continuously in the same molecule and having a viscosity at 25 ° C. of 10 to 1,000 poise and in one molecule At least 2
Or more vinyl group-containing structural units (CH ₂ = CH) (CH
₃ ) ₂ SiO _1/2 , (CH ₂ ＣＨCH) (CH ₃ ) Si
Resin-like polysiloxane containing O, (CH ₂ ＣＨCH) SiO _3/2 .

[0034] Te present invention smell, continuous this The oil segment in the component _{(2), (CH} 3) 2 SiO structural units represented by (bifunctional) at least 100 or more
It refers to a linear segment having been, in good Mashiku 300
It is preferable that the linear segments have at least one continuous segment.

Component (3): a hydrogenene polysiloxane having an average of more than one silicon-bonded hydrogen atom per molecule (preferably having a viscosity at 25 ° C. of 1-100 centipoise).

Component (4): Platinum catalyst.

The elastic body of the present invention comprises the above components (1) to
It is obtained by curing a homogeneous mixture based on (4). The curing mechanism is the same as that of a so-called addition type silicone rubber. Is added to form a network structure of the bound polysiloxane to become a rubber elastic body.

Component (1) is a component that greatly contributes to mold releasability. It is known that the linear dimethylpolysiloxane is effective in improving the releasability, but the effect of 80,000 poise or more is far beyond the expectation of the knowledge of the conventional low viscosity substance (molecular weight of 200,000 or less). It is a thing.

Conventionally, a dimethylpolysiloxane having both ends vinyl group-blocked, which has been used as a main component of an LTV (liquid rubber) material, has a viscosity of about 5 to 1,000 poise. The equivalents are known to be used in part as millable materials, but are not commonly used in LTV materials due to their high viscosity. The viscosity of the component (1) at 25 ° C. must be 80,000 poise or more, preferably 100,000 poise to 1
, 000,000 poise is good. The amount of component (1) is 1 in the mixture.
An amount occupying 0% by weight or more and less than 50% by weight is preferable,
More preferably, the content is 20 to 49% by weight. If it is less than 10% by weight, there is no effect, and if it is 50% by weight or more, the processability tends to decrease.

Component (2) is a component that reduces the viscosity of component (1) and contributes to the physical strength of the elastic body. As a method of improving the physical strength of silicone rubber, it is known to mix hydrous synthetic silicic acid or anhydrous synthetic silicic acid as a reinforcing agent. However, in the case of hydrous synthetic silicic acid, unless the amount of addition is as much as 20 to 50 parts by weight with respect to 100 parts by weight of dimethyl silicone rubber, not only the reinforcing effect is not exhibited, but the releasability is greatly reduced. Resulting in. In the case of anhydrous synthetic silicic acid, a small amount of addition, for example, 10 to 20 parts by weight, can provide some reinforcing effect as compared with hydrous synthetic silicic acid, but the releasability is still largely deteriorated, and therefore, the demolding property has hitherto been increased. There was no well-balanced property and physical strength.

The component (2) has a resin segment and an oil segment and essentially has a reinforcing effect. However, due to the entanglement effect of molecules with the component (1), the releasability and the physical strength are very good. It will be balanced.

In particular, a silicone resin containing a so-called ladder polymer composed only of the structural unit CH ₃ SiO _3/2 system, or a silicone resin containing a so-called block polymer having a resin segment and an oil segment in the same molecule, is used as a component ( It is suitable to reinforce 1). The viscosity at 25 ° C. of component (2) is preferably 10
~ 1,000 poise is good, more preferably 20 ~ 50
0 poise is good.

The blending amount of the component (2) is 50% by weight in the mixture.
The amount is more preferably 90% by weight or less, and more preferably 51 to 70% by weight. When the content is less than 50% by weight, the reinforcing effect is small, and when it exceeds 90% by weight, the releasability tends to decrease.

The weight ratio of the components (1) and (2) is preferably from 100: 101 to 900, more preferably from 100: 101 to 350.

Component (3) is a curing agent. If the amount of unreacted reactive groups remaining after curing is large, the releasability is adversely affected. Therefore, silicon-bonded hydrogen atoms to all vinyl groups in the mixture are used. The molar ratio is preferably 0.6 to 2.5, more preferably 1.0 to 2.0.

The platinum catalyst of the component (4) is effective for catalyzing the reaction with the vinyl-bonded silicon-bonded hydrogen atom, and the optimum amount of the catalyst to be added is determined from the viewpoint of processability and the like.

In the present invention, the above (1) to (4)
The viscosity of the polysiloxane mixture obtained by mixing the above components is preferably from 500 to 20,000 poise, more preferably from 1,000 to 10,000 poise.

In addition to the above basic constituents, a suitable amount of a low-molecular-weight terminal vinyl group-blocked linear dimethylpolysiloxane containing a side chain vinyl group is preferably blended for processability (viscosity control). .

Further, within a range not impairing the object of the present invention,
Adopt other reinforcing agents, or colorants, heat improvers,
A thixotropic agent or the like can be added.

The elastic body of the present invention can be applied to a member requiring elasticity such as a carrying roller, a fixing roller (particularly a fixing roller), a developing blade or a cleaning blade.

Next, a device specifically using the elastic body of the present invention will be described.

FIG. 1 is a schematic sectional view showing an embodiment of the fixing device of the present invention.

The fixing device has a fixing roller 1 and a pressure roller 2 as fixing rollers, and an oil coating device 3 for applying silicone oil as a release agent for releasing toner onto the surface of the fixing roller 1. Are arranged.

In the fixing roller 1, an elastic core layer 12 having HTV (millable type) silicone rubber is formed on a metal core 11 using aluminum as a core member, and a 50 μm oil barrier layer is formed on the elastic core layer 12 as an oil barrier layer. A fluororubber layer 13 having a layer thickness is formed. Further, an elastic layer 14 having a layer thickness of 400 μm and having an anti-offset property is formed on the fluororubber layer 13, and the elastic layer 14 is a specific addition type silicone rubber elastic body obtained from the polysiloxane mixture according to the present invention. It consists of The outer diameter of the fixing roller 1 is set to be, for example, 40 mm.

In the pressure roller 2, an elastic core layer 22 having HTV silicone rubber is formed on an aluminum cored bar 21 as a core member, and a fluororesin layer 23 as an oil barrier layer is formed on the elastic core layer 22. Has been formed. The outer diameter of the pressure roller 2 is set to be 40 mm, for example.

The core metal 11 of the fixing roller 1 and the pressure roller 2
A halogen heater 4 is disposed as a heating element in the metal core 21 of the fixing roller 1. In addition, the temperature of the pressure roller 2 is kept constant at, for example, 170 ° C.

The fixing roller 1 and the pressure roller 2 are driven to rotate in the direction of arrow b by a driving device (not shown).
The recording material P conveyed in the direction of the arrow a by the conveying device (not shown) is passed through the two rollers 1 and 2 while being pinched. As a result, the unfixed toner image T on the recording material P is It is fixed on the recording material P by the action of heat and pressure of 2.

The oil applicator 3 sucks up a release agent for offset prevention, such as dimethyl silicone oil or fluorosilicone oil, contained in the container 31, for example, dimethyl silicone oil, by the upper and lower supply rollers 32 and 33, and fixes the fixing roller 1 It is adapted to be applied to the surface of the elastic layer 14. The application amount of the silicone oil is adjusted by the contact angle and the pressure of the oil amount adjusting blade 34 in contact with the upper supply roller 33. Fixing roller 1 and pressure roller 2
May be provided with a cleaner for cleaning toner stains adhered to the roller surface.

In the above, the fixing roller 1 of the pair of rollers for fixing the toner on the recording material in the fixing device is described.
In the above description, the elastic layer made of the elastic material of the present invention is included. However, the elastic roller may be further applied to the pressure roller 2, and a pair of belt-shaped elastic members may be used instead of the pair of rollers. Can also be applied to one or both.

FIG. 2 is a schematic sectional view showing a developing device using the elastic body of the present invention as a developing blade.

In FIG. 2, reference numeral 101 denotes a photosensitive drum as an electrostatic latent image carrier which rotates in the direction of arrow A. The photosensitive drum 101 has a photosensitive member having an organic photoelectric layer formed on a cylindrical conductive substrate, and an electrostatic latent image is formed by electrostatic recording means (not shown).

A developing device is provided opposite to the photosensitive drum 101, and the developing device includes a developer supply container 102.
A developing sleeve 103 as a developer carrying member; a developing blade 104 as a developer regulating unit formed by the elastic body of the present invention; a supply roller 105 as a developer supplying unit; And a toner feeding member 106.

The container 102 has an opening extending in the longitudinal direction of the developing device (direction perpendicular to the paper surface), and the developing sleeve 103 is arranged in the opening. The developing sleeve 103 is made of a non-magnetic material such as aluminum or stainless steel. The developing sleeve 103 is rotatably supported, and is driven to rotate in the direction of arrow B by a driving source (not shown). On the surface of the developing sleeve 103, irregularities having a pitch of 0.5 to 5 mm are formed in order to ensure the holding of the toner.

The supply roller 105 is arranged behind the developing sleeve 103 so as to rotate in sliding contact at the sliding contact portion S. The supply roller 105 rotates in the C direction, which is the same direction as the developing sleeve 103, to supply the developer to the developing sleeve 103.
To the developing sleeve 103 and elastically contact with the developing sleeve 103, so that
The rotating toner that has not been consumed in the development in the developing unit P facing the photosensitive drum 101 is peeled off.

The supply roller 105 and the developing sleeve 1
The developing blade 104 is disposed downstream of the sliding contact portion S with the developing sleeve 103 in the rotation direction of the developing sleeve 103 such that its free end is in contact with the developing sleeve 103 at the contact portion T. At the contact portion T, the passage of the developer on the developing sleeve 103 is regulated.

The contact portion T is located on the supply roller 105 side and above the supply roller 105 with respect to the vertical line passing through the center of the developing sleeve 103, and the contact portion T and the sliding contact portion S.
Have a positional relationship such that the toner separated at the contact portion T can drop onto the supply roller 105. Thus, a smooth circulating flow of toner is formed in the space between the contact portion T and the sliding contact portion S.

A toner feeding member 106 is disposed in the container 102 behind the supply roller 105 so as to rotate in the direction of arrow D, and the magnetic toner 107, which is a one-component magnetic developer, is supplied to the supply roller 105.

Supply roller 105 and toner feed member 106
A guide wall 108 is provided between the supply rollers 1.
05, the toner separated by the toner feeding member 106
A flow path 109 for guiding the toner to a position where the toner is conveyed is formed.

The merged toner is supplied to the supply roller 10
5, the toner is conveyed again to the sliding contact portion S with the developing sleeve 103.
The amount is regulated by the regulating member 110 disposed above the.

Below the developing sleeve 103, the container 10
A seal member 111 for closing the gap with the second member 2 is provided.
The seal member 111 is a flexible sheet such as Mylar (trade name, manufactured by DuPont).

Further, the photosensitive drum 101 and the developing sleeve 10
A power supply 112 is disposed between the developing sleeve 10 and the developing sleeve 10.
A power source 113 is provided between the supply roller 105 and the supply roller 105, and the developing sleeve 103 and the supply roller 10 are provided respectively.
5, a bias voltage is applied.

FIG. 3 is a schematic sectional view showing a cleaning device using the elastic body of the present invention as a cleaning blade.

In FIG. 3, reference numeral 201 is a photosensitive drum that rotates in the direction of arrow X and serves as an electrostatic latent image carrier. The photosensitive drum 201 is arranged so that its axis extends in the horizontal direction, and the cleaning device 202 is arranged near the side thereof.

In the cleaning device 202, the cleaning blade 20 formed of the elastic body of the present invention is provided.
3, the magnet roller 204, and the conveying screw 205 are provided, and the residual toner not transferred to the recording material at the transfer position (not shown) of the photosensitive drum 101 moves to the position of the blade 203 as the photosensitive drum 101 rotates. When it arrives, it is scraped off from the photosensitive drum 201 by the blade 203. Further, attached foreign substances such as residual toner are mainly removed by the action of the magnet roller 204,
The toner is conveyed to the toner storage section by the action of the magnet roller 204, and further discharged out of the cleaning device by the screw 205 as necessary.

FIG. 4 is a schematic sectional view showing another embodiment of the fixing device of the present invention.

In the figure, reference numeral 301 denotes a fixing roller,
The fixing device includes a fixing roller 301 and a pressure roller 302 facing the fixing roller 301. The fixing roller 301 is formed by forming an elastic layer 306 on the surface of an aluminum core member 5 with an elastic body made of the addition type silicone rubber of the present invention to a predetermined thickness. The pressure roller 302 includes an elastic core layer 30 made of HTV silicone rubber on a core member 307 made of aluminum.
8 is formed to a predetermined thickness, and a resin coating 3 is further formed on the surface layer.
09 is formed.

In the fixing roller 301, a halogen heater 310 as a heating source is provided. Fixing roller 3
01 is in contact with the thermistor 316 and the thermistor 31
On / off of the current to the halogen heater 310 is controlled by 6. In this manner, the temperature of the fixing roller 301 changes the unfixed toner image 313 on the recording material 314 to the recording material 3.
Suitable temperature for fixing on 14 (eg 170 ° C)
Is to be kept. The fixing roller 301 and the pressure roller 302 are moved by arrows b ₁ , b
Rotated in _two directions.

On the other hand, a release agent applying device 303 is provided near the fixing roller 301 in order to improve the releasability of the toner from the fixing roller 301. In the release agent applying device 303, one end of the felt 311 is immersed in silicone oil 312 as a release agent contained in the oil tank 325, and the other end of the felt 311 is brought into contact with the surface of the fixing roller 301. Then, the oil 312 is applied onto the surface of the fixing roller 301 through the felt 311.

Further, the release agent applying device 3 of the fixing roller 301
On the side opposite to 03, a cleaning device 3 for cleaning the toner offset on the fixing roller 301.
04 are provided. The cleaning device 304 includes a non-woven fabric 319 for cleaning the surface of the fixing roller 301 and the pressing roller 31 for bringing the non-woven fabric 319 into contact with the surface of the fixing roller 301.
It consists of 8.

The recording material 314 carrying the unfixed toner image 313 is conveyed by a conveying device (not shown) in the direction indicated by the arrow f in FIG.
Between the fixing roller 301 and the pressure roller 302 which rotates in _1, g ₂ direction, is inserted as a contact side of the fixing roller 301 the toner image 313. While passing therethrough, the recording material 314 is pressed by the fixing roller 301 and the pressure roller 302 and heat controlled to a predetermined temperature supplied from the halogen heater 310 via the fixing roller 301. The unfixed toner image 313 is fixed on the recording material 314. The recording material 314 on which fixing has been completed is discharged out of the image forming apparatus via the exit guide 317.

FIG. 5 is a schematic sectional view showing still another embodiment of the fixing device of the present invention.

In this embodiment, the pressure roller 30 of the fixing device is used.
2 is also provided with a halogen heater 324, and the thermistor 316 abutted on the pressure roller 302 causes the halogen heater 310 and the pressure roller 302 in the fixing roller 301.
ON / OFF of the electric current to the halogen heater 324 therein is controlled. As a result, the fixing roller 301 and the pressure roller 3
The temperature 02 is maintained at a temperature (for example, 170 ° C.) suitable for fixing the unfixed toner image 313 on the recording material 314 onto the recording material 314.

Therefore, when the recording material 314 carrying the unfixed toner image 313 is inserted between the fixing roller 301 and the pressure roller 302 with the toner image 313 being the contact side with the fixing roller 301, the recording material 314 becomes the fixing roller 301. Pressure roller 30
2 and the halogen heaters 310 and 3 respectively.
The recording material 314 is fixed on the recording material 314 by heat of a predetermined temperature supplied from the fixing roller 301 and the fixing roller 301 and the pressure roller 302.

Further, in the present embodiment, the release agent coating device 303 provided near the fixing roller 301 draws up the silicone oil 312 in the oil tank 325 and draws up the roller 3.
The application roller 311 pumps the oil 312 to the fixing roller 3011 by pumping the oil 312 to the application roller 311 via the blades 22 and 321, and controlling the amount of coating by the blade 320 which is in contact with the application roller 311.
1 is applied.

The releasing agent applying device 303 is disposed so as to be capable of coming into contact with the fixing roller 301, and for example, the recording material 31.
When the recording material 314 exits from 1 cm before the sheet No. 4 enters between the fixing roller 301 and the pressure roller 302, the trailing end of the recording material 314 is 1 cm.
The silicone oil 312 is applied to the fixing roller 301 until the fixing roller 301 is apart from the fixing roller 301.

Further, in this embodiment, in order to clean the surface of the pressure roller 302, a blade 323 of a simple cleaning means is provided on the side of the pressure roller 302 opposite to the thermistor 316.

The other structure of the fixing device of this embodiment is basically the same as that of the embodiment of FIG.
The same reference numerals as those given to indicate the same members.

FIG. 6 is a schematic sectional view showing still another embodiment of the fixing device of the present invention.

This embodiment is a fixing device suitable for application to an image forming apparatus capable of performing double-sided copying.
Not only is the elastic layer 306 formed of an elastic body formed of the specific additional silicone rubber of the present invention, but also the elastic layer 329 of the pressure roller 303 is formed of the same elastic body formed of the additional silicone rubber of the present invention. It is a characteristic that FIG. 5 shows another configuration of the fixing device of this embodiment.
The same reference numerals as in FIG. 5 denote the same members in FIG. 6.

During double-sided copying, the toner image
The toner image 313 is fixed by inserting the recording material 314 having the toner image 313 formed on one surface thereof between the fixing roller 301 and the pressure roller 302 with the toner image 313 in contact with the fixing roller 301. . After that, a toner image similar to the toner image 313 is formed on the other surface of the recording material 314, and the recording material 314 is used as the fixing roller 301 with the toner image on the other surface as the contact side with the fixing roller 301. The toner image on the other side is fixed by being inserted between the pressure roller 302 and the fixing of the double-sided copy.

In the above, the tensile strength of the elastic layer of the fixing roller used in each of the fixing devices shown in FIGS. 1 and 4 to 6 is preferably 10 kgf / cm ² or more, more preferably 14 kgf / cm ^2. It is more preferably at least 20 kgf / cm ² .

Since the elastic body of the present invention is made of a specific addition type silicone rubber elastic material, it has excellent releasability and physical strength. Further, an elastic roller using the elastic body as an elastic layer on the surface thereof and a fixing device having the elastic roller are excellent in offset resistance, capable of favorably fixing an unfixed toner image on a recording material, and Does not stain the image. Further, it has excellent durability, and the toner image can be stably fixed on the recording material.

Hereinafter, specific examples of the present invention will be described, but they do not limit the present invention in any way.

Preparation of Polysiloxane Mixture 1 40 parts by weight of a linear dimethylpolysiloxane (p-1) having a viscosity of 100,000 poise and having a terminal vinyl group blocked at 25 ° C. and a viscosity of 300 poise at 25 ° C. 60 parts by weight of a resin-like organopolysiloxane (p-2), which is a block polymer having a resin segment having tetrafunctional and trifunctional units and a bifunctional oil segment in the same molecule, and a platinum catalyst, A polysiloxane mixture 1 was obtained by blending a crosslinking agent.

The platinum catalyst, the cross-linking agent (hydrogen polysiloxane having an average of more than one silicon-bonded hydrogen atom per molecule) is used to optimize the curability of the mixture.
What is necessary is just to select a kind and a compounding amount.

Preparation of Comparative Polysiloxane Mixtures 1 to 3
It was used in the preparation of manufacturing the polysiloxane mixture 1 (p-1) 40
Instead of parts by weight, linear dimethylpolysiloxane 4 with a terminal vinyl group endcaps having viscosities at 25 ° C. of 50 poise, 400 poise and 5,000 poise shown in Table 1, respectively.
Comparative polysiloxane mixtures 1, 2, and 3 were obtained in the same manner except that 0 parts by weight and 60 parts by weight of (p-2) were used.

Example 1, Comparative Examples 1, 2 and 3 Polysiloxane Mixture 1 and Comparative Polysiloxane Mixtures 1, 2 and 3 were used for press vulcanization at 130 ° C. for 30 minutes to obtain a 2 mm thick silicone rubber. Each sheet was obtained. Next, these sheets were subjected to secondary vulcanization at 200 ° C. for 4 hours, and then at room temperature according to JIS K6301.
The tensile strength was measured based on. Table 1 shows the results.

Further, a fixing roller was manufactured as described below using each of the above polysiloxane mixtures.

A heat-resistant HTV silicone rubber was vulcanized and bonded on a core member for a fixing roller made of a hollow aluminum alloy having an outer diameter of 34 mm by a known method, and a rubber roller having an outer diameter of 39 mm was obtained by polishing. Next, the roller surface is treated with a primer, and then fluororubber paint (GL-152 manufactured by Daikin Industries, Ltd.)
Was spray-coated to a thickness of 50 μm and dried at 150 ° C. for 30 minutes to obtain a fluororubber-coated rubber roller. Further, after applying the siloxane-based primer treatment to the fluororubber-coated rubber roller, it is disposed in a cylindrical mold that has been preheated to 130 ° C., and the polysiloxane mixture is injected into the mold and held for 30 minutes. And cured. The fixing roller coated with silicone rubber removed from the mold after curing,
The outer diameter was 40 mm and the silicone rubber elastic layer thickness was 3 mm.

After the fixing roller taken out from the mold as described above was subjected to secondary vulcanization at 200 ° C. for 4 hours, the fixing roller was used in the fixing device shown in FIG. Was performed. Table 1 shows the results.

The copy life test conditions using the fixing device shown in FIG. 1 are as follows.

Heater control temperature: 170 ° C. Pressing pressure of pressure roller: 40 kgf Paper passing paper: A4 size recording paper (84 g / m ² paper) on which unfixed color toner (magenta) image of test pattern is formed : 10 sheets / minute Release agent: dimethyl silicone oil Toner: 100 parts by weight of polyester based binder, 4 parts by weight of pigment (CI Solvent Red 49),
It was prepared using 0.7 parts by weight of a dye (CI Pigment Red 122), 4 parts by weight of a charge control agent, and an external additive.

Paper was continuously passed under the above conditions, and the number of sheets until the toner was offset on the fixing roller was defined as the copy life.

[0104]

[Table 1]

As is apparent from Table 1, the fixing roller having the silicone rubber elastic layer obtained from the polysiloxane mixture according to the present invention of Example 1 exhibited excellent copy life characteristics. The mechanical strength of the silicone rubber elastic layer was sufficient to withstand the above-mentioned copy life test, and in the heat resistance, there was no problem of deterioration or deterioration of the surface due to heat in the same test.

Preparation of Polysiloxane Mixture 2 (p-2) 60 used in preparation of polysiloxane mixture 1
Instead of parts by weight, vinyl group is a block polymer having a viscosity of 40 poise at 25 ° C. and having a resin unit having tetrafunctional and trifunctional functions and an oil segment having difunctional functions in the same molecule. Polysiloxane mixture 2 was obtained in the same manner except that 60 parts by weight of the contained resinous polysiloxane was used.

Preparation of Polysiloxane Mixture 3 (p-1) 40 used in preparation of polysiloxane mixture 1
30 parts by weight of (p-1) instead of parts by weight, and (p-2) 6
40 parts by weight of (p-2) instead of 0 parts by weight, and 25 ° C.
A polysiloxane mixture 3 was obtained in the same manner except that 30 parts by weight of a linear dimethylpolysiloxane having a viscosity of 10 poise and capped with a terminal vinyl group was used.

Preparation of Polysiloxane Mixture 4 (p-1) 40 used in preparation of polysiloxane mixture 1
30 parts by weight of (p-1) instead of parts by weight, and (p-2) 6
40 parts by weight of (p-2) instead of 0 parts by weight, and 25 ° C.
A polysiloxane mixture 4 was obtained in the same manner except that 30 parts by weight of a linear vinyl dimethylpolysiloxane endblocked with a side chain vinyl having a viscosity of 10 poise was used.

Preparation of Comparative Polysiloxane Mixture 4 (p-1) 40 used in the preparation of Polysiloxane Mixture 1
Instead of 60 parts by weight and (p-2) parts by weight, (p-
1) Comparative polysiloxane mixture 4 was obtained in the same manner except that 100 parts by weight were used.

Preparation of Comparative Polysiloxane Mixture 5 (p-1) 40 used in the preparation of polysiloxane mixture 1
60 parts by weight of (p-1) instead of parts by weight, and (p-
2) A comparative polysiloxane mixture 5 was obtained in the same manner except that 40 parts by weight of a resinous organosiloxane having a viscosity of 1 poise at 25 ° C. was used instead of 60 parts by weight.

Examples 2, 3 and 4, Comparative Examples 4 and 5 Polysiloxane Mixtures 2, 3 and 4, Comparative Polysiloxane Mixtures 4 and 5, respectively, were used in the same manner as in Example 1 to obtain a 2 mm thick silicone rubber. A sheet and a fixing roller were obtained. The tensile strength was measured using a rubber sheet in the same manner as in Example 1, and a copy life test was further performed using a fixing roller. Table 2 shows the results.

[0112]

[Table 2]

As is apparent from Table 2, the fixing roller having the silicone rubber elastic layer obtained from the polysiloxane mixture according to the present invention had excellent characteristics in copy life. The fixing roller shown in the second embodiment is the same as the first embodiment.
The copy life was slightly lower than that of the fixing roller, but it has low viscosity, excellent processability, and excellent mechanical strength, and can withstand the above copy life test. In the same test, there was no problem such as deterioration and deterioration of the surface due to heat. The silicone rubber elastic bodies of Examples 3 and 4 are different in Example 1 from the viewpoint of tensile strength.
The wear resistance of the roller surface was inferior in the copy life because it was slightly lower than that of the elastic body of No. 1, but it was at a level with no problem in practical use.

The silicone rubber elastic body obtained from Comparative Example 4 has a low strength and cannot withstand the above-mentioned tensile strength measurement. It is difficult to cast it into a mold due to its high viscosity at the time of fixing roller production. Because of the absence of such a mold, adverse effects such as collapse of the mold at the time of demolding are caused, and there is a problem in manufacturing.

Preparation of Polysiloxane Mixture 5 To 20 parts by weight of linear dimethylpolysiloxane having a vinyl end blocked with a vinyl group having a viscosity of 200,000 poise at 25 ° C., 25 ° C.
The structural unit having a viscosity of 40 poise is tetrafunctional, and a resin-containing segment having trifunctionality and an oil segment having bifunctionality in the same molecule are block polymers having a vinyl group-containing resinous polyorganosiloxane of 40 parts by weight, A base oil having a viscosity of 5 poise at 25 ° C. and 40 parts by weight of a linear dimethylpolysiloxane end-blocked with a vinyl group was obtained, and then 20 parts by weight of quartz powder, a platinum catalyst and a crosslinking agent were added to 100 parts by weight of the base oil. A polysiloxane mixture 5 containing (hydrogenpolysiloxane having an average of more than one silicon-bonded hydrogen atom per molecule) was obtained.

Example 5 Polysiloxane mixture 5 was press-vulcanized at 130 ° C. for 30 minutes to obtain a 2 mm thick silicone rubber sheet.
Further, the obtained silicone rubber sheet was subjected to secondary vulcanization at 200 ° C. for 4 hours and then cut into a width of 20 mm to obtain a rubber blade having a hardness of 50 ° (JISA). The obtained rubber blade was used as a developing blade in the developing device shown in FIG.

In this embodiment, a developing sleeve having a diameter of 2
A 0 mm aluminum sleeve surface was roughened with a # 600 sandpaper to form irregularities with a pitch of 1.5 μm.

The non-magnetic toner used in the present embodiment has an average particle diameter of 7 parts mainly composed of 10 parts of carbon and 90 parts of polystyrene.
Approximately 1.0% by weight of silica as an external additive was used as an external additive to give fluidity to the toner. A thin Mylar seal having a thickness of 50 μm was used as a seal member for preventing the toner from scattering from the container. The contact pressure of the developing blade against the developing sleeve is
Approximately 5 to 100 when changing the hardness and size of the blade
g / cm is effective and 5 in the longitudinal direction of the developing sleeve.
It is preferable to keep the error within g. About 45 in the experimental example
It was set to g / cm. Foam diameter 1mm as supply roller
Everlite material (trade name, manufactured by Bridgestone Corporation) is wound on a stainless steel cored bar having a diameter of 6 mm, and a diameter of 14 mm.
A sponge roller in the form of a mm roller was used. The developing sleeve was rotated at 120 mm / sec, and the supply roller was rotated at a relative speed of 50 to 300 mm / sec with respect to the developing sleeve. The following results are obtained when 70 mm / sec is set. As a result of conducting the experiment in this way,
30-100 μm without streaks or unevenness on the surface of the developing sleeve
It was possible to form a thin toner layer. It was also confirmed that the layer thickness of the toner can be changed by changing the linear pressure of the developing blade.

In this experimental example, the thickness of the toner layer on the developing sleeve is made smaller than the gap between the opposing gaps between the developing sleeve and the photosensitive drum, and the toner is moved from the developing sleeve to the photosensitive drum in the gap to perform development (so-called “so-called”). Non-contact development or jumping development) was used.

In this experimental example, the dark area was +6 on the photosensitive drum.
An electrostatic latent image of 00 V and a bright portion of 0 V is formed, the gap between the photosensitive drum and the developing sleeve is maintained at about 300 μm, the toner layer thickness is regulated at 50 μm, and the peak / peak voltage 140
+150 for rectangular wave alternating voltage of 0V and frequency of 1800Hz
A developing bias on which a DC voltage of V was superimposed was applied to the developing sleeve, and development was performed at a process speed of 100 mm / sec.

As a result of continuous image formation on 50,000 sheets, uneven development of image density due to adhesion or fusion of toner to the blade did not occur, and good development could be performed.

Preparation of Polysiloxane Mixture 6 At 25 ° C., 20 parts by weight of a linear dimethylpolysiloxane having a viscosity of 200,000 poise and having a terminal vinyl group blocked were added at 25 ° C.
A vinyl group-containing resin-like polyorganosiloxane 3 which is a block polymer having a resin segment having a tetrafunctionality and a trifunctionality and a difunctional oil segment in the same molecule as a constituent unit having a viscosity of 40 poise
0 parts by weight, a base oil using 50 parts by weight of a linear dimethylpolysiloxane endblocked with a vinyl group having a viscosity of 5 poise at 25 ° C., and then 20 parts by weight of quartz powder based on 100 parts by weight of the base oil, 5 parts by weight of reinforcing silica fine powder (specific surface area 110 m ² / g, average particle size about 16
Thus, a polysiloxane mixture 6 was prepared which contained a silicic acid anhydride having a surface methylation of .mu.m), a platinum catalyst and a crosslinking agent (a hydrogenene polysiloxane having an average of more than one silicon-bonded hydrogen atom per molecule).

Example 6 The polysiloxane mixture 6 was press-vulcanized at 130 ° C. for 30 minutes to obtain a silicone rubber sheet having a pressure of 3 mm.
Further, the obtained silicone rubber sheet was subjected to secondary vulcanization at 200 ° C. for 4 hours, and then cut at a width of 15 mm to obtain a rubber blade having a hardness of 55 ° (JISA). The obtained rubber blade was used as a cleaning blade in the cleaning device shown in FIG.

The above cleaning blade was subjected to an actual machine durability test under the following conditions.

Contact angle with photosensitive drum: 25 ° Contact pressure (linear pressure): 20 g / cm Blade free length: 5 mm Toner: polystyrene-based toner having an average particle diameter of 12 μm Process speed: 20 mm / sec

As a result of the durability test of 50,000 sheets continuously, no problems such as defective cleaning due to toner adhesion and reversal turning of the cleaning blade due to an increase in frictional force with the photosensitive drum did not occur at all.

Examples 7, 8, and 9 After a siloxane-based primer treatment was performed on a core member for a fixing roller made of a hollow aluminum alloy having an outer diameter of 58 mm,
The siloxane mixtures 1, 2, and 3 were placed in a cylindrical mold that had been preheated to 0 ° C., respectively, injected into the mold, and held for 30 minutes to cure. The fixing roller covered with silicone rubber removed from the mold after curing has an outer diameter of 60 mm and a thickness of the silicone rubber elastic layer of 1 m.
m.

The fixing roller taken out of the mold was
After secondary vulcanization at 00 ° C. for 24 hours, a durability test was performed using the fixing roller in a fixing device shown in FIG. 4 under the following conditions.

Heater control temperature: 180 ° C. Pressing pressure of pressure roller: 60 kgf Paper passing paper: A4 size recording paper (64 g / m ² paper) on which unfixed magnetic toner image of test pattern was formed Release agent: viscosity at 25 ° C. Is 450 cs, and the number of moles of phenyl group is 25 mol. Phenyl silicone oil Paper passing speed: 40 sheets / min. Toner: black toner. 100 parts by weight of polyester-based main binder, 60 parts by weight of magnetic material, charge control agent 2
It was prepared using 3 parts by weight of a fixing aid and 3 parts by weight of an external additive.

In the fixing apparatus using the additional type silicone rubber of the seventh embodiment for the elastic layer of the fixing roller, fixing is performed using the additional type silicone rubber of the eighth embodiment for the elastic layer of the fixing roller up to 1,000,000 sheets. No offset phenomenon occurs on the fixed image up to 950,000 sheets in the fixing device, and up to 970,000 sheets in the fixing device using the additional type silicone rubber of the ninth embodiment for the elastic layer of the fixing roller.
Excellent fixability was achieved. Further, in the fixing rollers used in Examples 7, 8 and 9, the elastic layer of the fixing roller did not always swell with silicone oil throughout the durability test, and a good image was obtained by fixing.

Example 10 Instead of the phenyl silicone oil used in Example 7,
The viscosity at 25 ° C. is 450 cs and the number of moles of phenyl group is 1
0 mol of phenylmethyl silicone oil was used. Otherwise, the fixing durability test was performed in the same manner as in Example 7.

As a result, the number of fixed sheets is 10 as in the seventh embodiment.
No offset phenomenon occurred on the fixed image up to 100,000 sheets, and excellent fixability was exhibited. Further, in all of the fixing rollers used in this Example 10, the elastic layer of the fixing roller was not swelled by the silicone oil throughout the durability test, and a good image was obtained by fixing.

Example 11 Instead of the phenyl silicone oil used in Example 7,
Viscosity at 25 ℃ is 300 cs, the number of moles of phenyl group is 2
5 mol of phenylmethyl silicone oil was used. Otherwise, the fixing durability test was performed in the same manner as in Example 7.

As a result, the number of sheets to be fixed was 10
No offset phenomenon occurred on the fixed image up to 100,000 sheets, and excellent fixability was exhibited. Further, in all of the fixing rollers used in this Example 11, through the durability test, the elastic layer of the fixing roller was not swelled by the silicone oil at all times, and a good image was obtained by fixing.

Reference Example 7 The procedure of Example 7 was repeated except that dimethyl silicone oil was used in place of the phenyl silicone oil used in Example 7.
When a fixing durability test was performed in the same manner as described above, the outer diameter of the fixing roller was changed due to swelling of the elastic layer.
The rubber has peeled off.

Comparative Example 6 An elastic layer of silicone rubber was formed on a core member in the same manner as in Example 7, except that Polysiloxane mixture 1 for comparison was used instead of Polysiloxane mixture 1 used in Example 7. A fixing roller was obtained. Then, a durability test was conducted in the same manner as in Example 7 except that the fixing roller was used in the fixing device shown in FIG.

As a result, the offset phenomenon occurred on the fixed image after fixing 200,000 sheets, and the durability was poor.

Embodiments 12, 13 and 14 The fixing rollers used in Embodiments 7, 8 and 9 are shown in FIG.
A durability test was performed under the following conditions using the fixing device shown in FIG.

Heater control temperature: fixing roller 150 ° C., pressure roller 150 ° C.

Pressing pressure of pressure roller: 50 kgf Paper passing paper: A4 size recording paper (80 g / m ² paper) on which unfixed toner images (magenta, cyan, yellow and black) of the test pattern are formed Release agent: 25 Phenyl silicone oil having a viscosity at 450 ° C. of 450 cs and the number of moles of phenyl group being 25 mol Paper passing speed: 5 sheets / min The magenta toner comprises 100 parts by weight of a polyester-based main binder, pigment C.I. I. Solvent Red 49 4 parts by weight, dye C.I. I. 0.7 parts by weight of CI Pigment Red 122,
A charge control agent was prepared using 4 parts by weight and an external additive. Cyan toner is polyester main binder 10
To 0 parts by weight, 5 parts by weight of a phthalocyanine pigment, 4 parts by weight of a charge control agent and an external additive were prepared. The yellow toner is prepared by adding 100 parts by weight of a polyester-based main binder to C.I. I. Pigment Red 17 was used in an amount of 5 parts by weight, a charge control agent in an amount of 4 parts by weight, and an external additive. Black toner is a polyester-based main binder 10
5 parts by weight of carbon black, 4 parts by weight of a charge control agent and 0 part by weight of an external additive were prepared.

In the fixing device using the elastic body formed of the polysiloxane mixture 1 of Example 12 as the elastic layer of the fixing roller, no offset phenomenon occurred on the fixed image up to 80,000 sheets. Furthermore, when the elastic body formed of the polysiloxane mixture 2 of this Example 13 is used for the elastic layer of the fixing roller, and when the elastic body formed of the polysiloxane mixture 3 of this Example 14 is used for the elastic layer of the fixing roller. In this case, similarly, no offset phenomenon occurred on the fixed image up to 80,000 sheets. In each case, the fixing roller exhibited excellent fixing properties, and there was no problem in both the durability and the abrasion resistance of the elastic layer, and the life of the fixing roller could be drastically extended.

Further, all the fixing rollers used in Examples 12, 13 and 14 did not swell with silicone oil in the elastic layer of the fixing roller during the durability test, and a good image was obtained by fixing.

Comparative Example 7 Fixing having an elastic layer of silicone rubber on the core member in the same manner as in Example 10 except that the polysiloxane mixture 1 for comparison was used in place of the polysiloxane mixture 1 used in Example 10. Got Laura. Then, a durability test was conducted in the same manner as in Example 12 except that the fixing roller was used in the fixing device shown in FIG.

As a result, the offset phenomenon occurred on the fixed image after fixing 30,000 sheets, and the durability was poor.

Examples 15, 16 and 17 The fixing rollers used in Examples 7, 8 and 9 are shown in FIG.
In addition to the fixing device shown in FIG. 6, the elastic layer of the pressure roller is formed by using the polysiloxane mixtures 1, 2 and 3, and the pressure roller is used in the fixing device of FIG. Was established on both sides. Others are the same as in Examples 12, 13 and 14 using the fixing device of FIG.
A fixing durability test was conducted. When an offset occurred during the durability test, the fixing roller was replaced with a new roller, and the test was continued.

As a result, in the fixing device using the elastic body formed of the polysiloxane mixture 1 in the elastic layers of both the fixing roller and the pressure roller of the fifteenth embodiment, the number of double-sided images fixed is up to 500,000. No image contamination due to toner contamination of the roller occurred. Furthermore, the polysiloxane mixture 2 was used in the elastic layers of both the fixing roller and the pressure roller of this Example 16.
In the fixing device using the elastic body formed in 1. and the fixing device using the elastic body formed of the polysiloxane mixture 3 in the elastic layers of both the fixing roller and the pressure roller of Example 17,
In each case, no image contamination was caused by toner contamination of the pressure roller up to 500,000 sheets.

Comparative Example 8 A fixing roller used in Comparative Example 7 is used in the fixing device shown in FIG. 6, and a pressure roller using an elastic body formed of comparative polysiloxane mixture 1 in an elastic layer is shown in FIG. A durability test was conducted in the same manner as in Example 15 except that the fixing device was used.

As a result, the image was stained by toner stains on the pressure roller after fixing 100,000 sheets, and the durability was poor.

[0149]

As described above, since the elastic body of the present invention is formed of an addition type silicone rubber elastic material obtained from a specific polysiloxane mixture, it has excellent releasability and physical strength. ing. Therefore, the elastic roller using the elastic body as the elastic layer on the surface and the fixing device having the elastic roller are excellent in offset resistance and can satisfactorily fix the unfixed toner image on the recording material, and Does not stain the image. Further, it has excellent durability, and the toner image can be stably fixed on the recording material.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing one embodiment of a fixing device of the present invention.

FIG. 2 is a schematic cross-sectional view showing a developing device using the elastic body of the present invention as a developing blade.

FIG. 3 is a schematic cross-sectional view showing a cleaning device using the elastic body of the present invention as a cleaning blade.

FIG. 4 is a schematic sectional view showing another embodiment of the fixing device of the present invention.

FIG. 5 is a schematic sectional view showing still another embodiment of the fixing device of the present invention.

FIG. 6 is a schematic sectional view showing still another embodiment of the fixing device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 301 Fixing roller 2, 302 Pressure roller 3, 303 Oil coating device 4 Heater 14, 306 Elastic layer 104 Developing blade 203 Cleaning blade 310, 324 Heater 329 Elastic layer

 ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hideo Kawamoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) Reference JP-A-52-13547 (JP, A) JP-A 2-153969 (JP, A) JP-A-1-299827 (JP, A)

Claims (17)

(57) [Claims] 1. An elastic body formed of an addition-type silicone rubber elastic material, wherein the addition-type silicone rubber elastic material comprises: (a) a linear vinyl-blocked linear polymer having a viscosity at 25 ° C. of 80,000 poise or more. A dimethylpolysiloxane, and (b) a resin segment having two or more vinyl groups and containing at least one of tetrafunctional or trifunctional and a straight chain having at least 100 or more difunctional constituent units continuously. An elastic body comprising a cured product of a polysiloxane mixture having at least a resin-like organopolysiloxane having a viscosity of 10 poise or more at 25 ° C. having a block copolymer having the same oil segment in the same molecule. 2. The elastic body according to claim 1, wherein the resin-like organopolysiloxane contains a ladder polymer. 3. The elastic body according to claim 1, wherein the resin-like organopolysiloxane has a viscosity at 25 ° C. in the range of 10 to 1000 poise. 4. The polysiloxane mixture comprises a linear dimethylpolysiloxane having a viscosity at 25 ° C. of 100 poise or less and having a terminal vinyl group blocked or a linear dimethylpolysiloxane having a viscosity at 25 ° C. of 100 poise or less having a side chain of vinyl group 2. The elastic body according to claim 1, comprising at least one of dimethylpolysiloxane. 5. An elastic roller for fixing an unfixed toner image carried on a recording material to the recording material, wherein the elastic roller comprises a core member and an addition type silicone rubber on the surface side of the core member. The addition-type silicone rubber elastic material has an elastic layer formed of an elastic material, and the addition-type silicone rubber elastic material is (B) a resin segment having two or more vinyl groups and containing at least one of tetrafunctionality or trifunctionality, and a linear oil segment having at least 100 difunctional constituent units continuously. A polysiloxane blend having at least a resin-like organopolysiloxane having a viscosity of 10 poise or more at 25 ° C. having a block copolymer contained in the same molecule. An elastic roller having a cured product of a compound. 6. The elastic roller according to claim 5, wherein the viscosity of the resinous organopolysiloxane at 25 ° C. is in the range of 10 to 1000 poise. 7. The elastic roller according to claim 5, wherein the elastic roller further has an elastic core layer and an oil barrier layer between the core member and the elastic layer in order from the core member side. 8. The elastic roller further has an elastic core layer between the core member and the elastic layer.
Elastic roller. 9. A fixing device for fixing an unfixed toner image carried on a recording material to the recording material by heating and pressurizing the unfixed toner image, wherein the fixing device carries the unfixed toner image. For holding and heating the recording material, at least one of which has a heating means inside and is rotatable in pressure contact with each other, and contacts the unfixed toner image and the opposite side thereof, respectively. And a fixing unit having a pair of rollers including a fixing roller and a pressure roller on a side of the fixing member. The fixing roller includes a core member and an elastic layer formed of an additional silicone rubber elastic material on the surface side of the core member. The addition-type silicone rubber elastic material comprises (a) a linear vinyl dimethylpolysiloxane with a vinyl group-terminated end group having a viscosity at 25 ° C. of 80,000 poise or more, and (b) In the same molecule, a resin segment having two or more nyl groups and containing at least one of tetrafunctional or trifunctional and a linear oil segment having at least 100 or more continuous bifunctional constituent units in the same molecule A fixing device comprising: a cured product of a polysiloxane mixture having at least a resin-like organopolysiloxane having a viscosity at 25 ° C. of 10 poise or more, which has a block copolymer having the above-mentioned structure. 10. The fixing device according to claim 9, wherein the resin-like organopolysiloxane has a viscosity at 25 ° C. within a range of 10 to 1000 poise. 11. The fixing device according to claim 9, wherein the fixing roller has a heating unit inside. 12. The fixing device according to claim 9, wherein the fixing roller and the pressure roller have heating means inside. 13. The fixing device according to claim 9, wherein the fixing roller further has an elastic core layer and an oil barrier layer between the core member and the elastic layer in order from the core member side. 14. The fixing device according to claim 13, wherein the fixing roller fixes an unfixed toner image carried on a recording material in a state where a release agent is applied to a surface of the fixing roller. 15. The fixing device according to claim 9, wherein the fixing roller further has an elastic core layer between the core member and the elastic layer. 16. The fixing device according to claim 15, wherein the fixing roller fixes an unfixed toner image carried on a recording material in a state where a release agent is applied to the surface of the fixing roller. 17. The fixing device according to claim 16, wherein the release agent contains phenyl silicone oil.