JP3357999B2 - Fixing elastic roll with oil supply function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a releasability and heat resistance which can be favorably used for a fixing roll such as a pressure roll and a heating roll of an electrophotographic copying machine, a roll for a printing machine or a platen roll for a printing printer. The present invention relates to an elastic roll having excellent properties and durability and further having an oil supply function.

[0002]

2. Description of the Related Art Conventionally, a solid roll made of a simple material such as urethane rubber, ethylene propylene rubber, silicone rubber, or fluoro rubber has been used as this kind of fixing elastic roll. The fixing elastic roll made of these materials has a problem in releasability. If the releasability is poor, adhesion of toner and the like, adhesion of paper powder and the like, wrapping around a roll, and the like occur, which leads to deterioration of image quality and
There was a problem that the roll exchange cycle (life) was shortened.

In order to solve this problem, there has been proposed a solid roll provided with a coating layer made of silicone rubber, fluororesin, or the like having excellent releasability on the surface. This type of solid roll has improved releasability, heat resistance, and durability, and satisfies the needs as a conventional elastic roll for fixing.

However, recently, new needs have arisen, such as increasing the copy speed, making the apparatus compact (saving space), and copying one sheet of paper having a difference in thickness. To respond to the increase in copy speed with the solid roll,
Although it is advantageous to increase the nip width, the material is solid and lacks flexibility. To increase the nip width, (a) increase the contact pressure with the mating roll, (b) increase the roll diameter It is necessary to take measures such as However, when the means (a) is taken, there is a problem that the rolls are worn quickly and the durability is poor, and when the means (b) is taken, there is a recent need for a more compact apparatus. It will go backwards. Further, when a copying machine having the above-mentioned solid roll is used to copy an object having a difference in thickness, wrinkles are generated and the quality of a copied image is deteriorated.

[0005] In order to respond to the newly born needs, a sponge roll using a soft sponge (porous) material as a roll material has been proposed (Japanese Patent Application Laid-Open No. 58-17129). . By using this sponge roll, it is possible to increase the nip width without increasing the contact pressure with the partner roll or increasing the roll diameter, and wrinkles are generated when printing on objects with different thicknesses. It can be expected to do without. However, when the sponge roll is composed only of the sponge material, there is a problem in the releasability, which causes problems such as the occurrence of surface irregularities. In order to improve this point, a sponge roll provided with a coating layer made of silicone rubber or fluororesin having releasability on the surface has been proposed (the former is disclosed in Japanese Utility Model Application Laid-Open No. 59-393).
No. 15, JP-A-58-23072, and the latter is disclosed in JP-A-59-172668.

However, a sponge roll provided with a coating layer made of silicone rubber tends to swell due to release oil applied to a fixing roll or the like, lacks durability, and the thickness of the coating layer cannot be reduced due to processing. There was a problem that the characteristics of the base sponge could not be fully utilized.
Further, a sponge roll provided with a coating layer made of a fluororesin has a large coating applied to the interface between the coating layer and the underlying sponge because the coating layer is hard, and the coating layer is easily peeled off. However, there is a problem that the characteristics of the base sponge cannot be fully utilized because the base material cannot be made thinner due to processing.

On the other hand, in a fixing roll of a copying machine or the like, oil is applied to the surface of the fixing roll using an oil applying roll in order to prevent toner adhesion or roll wear. The oil application roll is required to continuously supply an appropriate amount (trace amount) of oil over a long period of time. That is, if the supply of oil to the fixing roll surface is excessive, the oil adheres to the copy paper to cause fouling or swelling of the roll surface material, and if the supply of oil is too small, offset occurs. In addition, the prevention of abrasion of the fixing roll becomes insufficient and the life of the fixing roll is shortened. For this reason, the oil application roll has conventionally been configured and used as a member separate from the fixing roll. However, in order to reduce the cost by reducing the number of parts related to the fixing unit or to reduce the size of the apparatus,
It has been desired that the fixing roll itself has an oil applying function without using the oil applying roll as a separate member from the fixing roll. However, in reality, no proposal has been made so far for a fixing roll, particularly a fixing roll composed of a sponge roll, having a function of continuously supplying an appropriate amount of oil for a long period of time.

[0008]

SUMMARY OF THE INVENTION In view of the state of the prior art, the present invention is excellent in mold releasability, durability and heat resistance, and can sufficiently cope with the recent needs described above.
Moreover, it is an object of the present invention to provide a fixing elastic roll having the function of continuously supplying an appropriate amount of oil for a long period of time, while solving the above-mentioned problems of a sponge roll having a coating layer. I do.

[0009]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have completed the present invention. That is, according to the present invention, in a fixing elastic roll in which a coating layer having releasability is provided on the surface of an elastic layer made of a thick porous tissue material , the thick porous tissue material is made of silicone rubber. Foam, thermosetting resin foam,
Or, the heat-resistant resin is coated on the surface of the polymer foam skeleton.
The cross-linked silicone rubber containing a release oil is filled in the void tissue of the thick porous tissue material, and the coating layer is stretched.
Porous polytetrafluoroethylene, porous expanded polytetrafluoroethylene and complex with the silicone rubber, or oil supply, characterized by comprising a complex of a stretched porous polytetrafluoroethylene and the release oil and silicone rubber An elastic roll for fixing having a function is provided.

Hereinafter, the present invention will be described in detail. The fixing elastic roll according to the present invention is a fixing elastic roll in which a coating layer having releasability is provided on the surface of an elastic layer made of a thick porous tissue material, wherein the thick porous tissue material has open cells. A cross-linked silicone rubber containing a mold release oil is filled in the void tissue of the thick porous tissue material, and the coating layer is formed of expanded porous polytetrafluoroethylene and expanded porous poly. It is characterized by comprising a composite of tetrafluoroethylene and silicone rubber or a composite of expanded porous polytetrafluoroethylene, release oil and silicone rubber. The elastic layer and the coating layer are provided on the cored bar.

First, the elastic layer will be described. In the present invention, a thick porous tissue material is used as the elastic layer. As the thick porous tissue material, a silicone rubber foam, a thermosetting resin foam, or a polymer foam having a skeleton surface coated with a heat-resistant resin is preferably used. These foams are open-cell foams, which are rich in elasticity and resilience, have a porosity of 30 to 95%, preferably 50 to 90%, and have a surface rubber hardness of 70 degrees or less, Preferably, the angle is 50 degrees or less. Closed-cell foams are not sufficient for providing the oil supply function of the present invention and are not adopted. If the porosity exceeds 95%, the structure and structure become brittle and the durability becomes poor. If the porosity is less than 30%, it is difficult to secure a bubble structure, and desired elasticity and restoring force cannot be obtained. It is not preferable from the viewpoint of proper holding and supply of the release oil. If the surface hardness exceeds 70 degrees, the elasticity is poor, and it is difficult to exhibit flexibility. In the present invention, the hardness is measured by S
According to RIS (Japan Rubber Association Standard) -0101. Also,
The thickness of the elastic layer is suitably from 5 to 30 mm.

As the silicone rubber foam, RTV
An open-cell foam of silicone rubber such as (room temperature curing type), LTV (low temperature curing type), HTV (heat curing type), and ultraviolet curing type can be used.

As the thermosetting resin foam, open-cell foams such as melamine, polyimide, phenol and bismaleimide resins can be used.

Examples of the polymer foam having a skeleton surface coated with a heat-resistant resin include polyester-based polyurethane, polyether-based polyurethane, polyvinyl chloride, and the like.
A polymer foam such as polyethylene or polystyrene having an open-cell structure but having a skeleton surface coated with a heat-resistant resin can be used. in this case,
As a heat-resistant resin to coat the polymer foam skeleton surface,
Any material having heat resistance and high elasticity can be used, but silicone rubber is particularly preferably used. The coating method is described in, for example, JP-A-58-1
A known method disclosed in, for example, US Pat. No. 7129 can be used.

As the silicone rubber to be coated on the surface of the foam skeleton, silicone rubbers such as RTV (room temperature curing type), LTV (low temperature curing type), HTV (heat curing type) and ultraviolet curing type can be used. . The coating amount of the silicone rubber is 50 to 300 kg / m ³ , preferably 100
２００200 kg / m ³ . When the coating amount exceeds 300 kg / m ³ , the volume of the voids of the foam decreases, and the elasticity and the restoring force become insufficient, so that sufficient flexibility cannot be obtained. On the other hand, if it is less than 50 kg / m ³ , a sufficient covering effect cannot be obtained, and sufficient heat resistance and durability cannot be obtained.

Here, the silicone rubber used in the present invention will be described in detail. (a) RTV-type silicone rubber A silicone rubber that undergoes a curing reaction at room temperature to become a rubber elastic body, and includes a one-pack type and a two-pack type. The one-component type RTV silicone rubber basically contains a reactive polysiloxane or a reactive fluoropolysiloxane, a curing catalyst and a crosslinking agent, and when exposed to air, a curing reaction occurs due to moisture in the air, resulting in a rubber elastic material. Becomes This one
Most liquid type RTV silicone rubbers are of the condensation reaction type. Depending on the type of cross-linking agent used, there are dealcoholized type that produces alcohol as a by-product, deoxime type that produces oxime as a by-product, and deacetic acid type that produces acetic acid as a by-product. In addition, there are a deamidation type, a deamidation type, and a deacetone type which by-produce amide, amine and acetone respectively. In the case of the dealcoholized type, the moisture in the air causes a hydrolysis reaction with the alkoxy group, and the portion where the alkoxy group exists serves as a cross-linking point, so that a network structure is formed one after another to become a rubber elastic body. In the case of other types, a rubber elastic body is formed by a similar reaction. The two-component type RTV silicone rubber basically comprises a liquid or paste-like base material containing a reactive polysiloxane or a reactive fluoropolysiloxane, and a curing agent, and forms the reactive polysiloxane or the reactive fluoropolysiloxane. It becomes a rubber elastic body by reacting in the presence of a curing catalyst. The curing catalyst and the crosslinking agent may be contained in either the base material or the curing agent, respectively. This two-liquid type RT
The V silicone rubber is a so-called deep curing type in which the curing reaction proceeds as a whole, unlike the one-component type, and when classified by curing mechanism, there are a condensation reaction type and an addition reaction type. In the case of the condensation reaction type, there are a dealcoholized type that produces alcohol as a by-product, a dehydroxylated amine type that produces hydroxylamine as a by-product, and a dehydrogenated type that produces hydrogen as a by-product, depending on the type of crosslinking agent used. In the case of the dealcohol type, a condensation reaction occurs by mixing the main agent and the curing agent, alcohol is by-produced, and a network structure is successively formed to become a rubber elastic body. In the case of other types, a rubber elastic body is formed by a similar reaction. In the case of the addition reaction type, the addition reaction proceeds under a noble metal catalyst by mixing the main agent and the curing agent,
It becomes a rubber elastic body. In this case, no by-products are generated. (b) LTV type silicone rubber The curing mechanism is the same as that of the RTV type, but it is a type in which the curing proceeds rapidly by adding a curing agent and then heating to 100 to 150 ° C. (c) HTV type silicone rubber containing high degree of polymerization polyorganosiloxane and vulcanizing agent;
By heating to 0 ° C. or more, vulcanization proceeds to form a rubber elastic body, which is also called a heat vulcanization type. The HTV type has a radical reaction type and an addition reaction type when classified according to the curing mechanism.
The radical reaction type is common and practical. In this radical reaction type, an organic peroxide is used as a vulcanizing agent, and the vulcanizing agent decomposes when heated to a decomposition temperature or higher in rubber to generate free radicals. These free radicals excite the organic groups of the silicone polymer, and a network structure is formed one after another to become a rubber elastic body. (d) Ultraviolet-curable silicone rubber A curing reaction is induced by irradiating ultraviolet rays to become a rubber elastic body.

The elastic layer of the present invention is in a state where the void structure of the foam is filled with a crosslinked silicone rubber containing a release oil. As the silicone rubber used in this case, the same RTV (room temperature curing type), LTV (low temperature curing type), HTV (heat curing type),
A silicone rubber such as an ultraviolet curing type is suitable. Also,
The release oil has a function of preventing toner from adhering to the fixing roller and preventing abrasion of the fixing roller, and silicone oil, particularly dimethyl silicone oil, is often used. The mixture of the silicone rubber and the release oil changes its state from a solid state to a gel state according to the mixture ratio. However, in the elastic layer of the present invention, the mixture ratio of the silicone rubber and the release oil (weight ratio; hereinafter the same) ) Is 90:10
2:98, preferably 50:50 to 5:95. The mixing ratio is 90: If 10 of silicone rubber is increased, moving from the mixture of release oil that is contained in the silicone rubber to the roll surface is extremely slowed, 2: 9
If the silicone rubber is less than 8, the release oil contained in the silicone rubber cannot be contained completely, and the silicone rubber is in an ungelled state, which causes oil leakage. Also,
The content of the mixture of the silicone rubber and the release oil is such that the proportion of the pores of the foam is 30 to 90%, preferably 50 to 80%. This ratio is 90
%, The remaining pores cannot absorb the increased volume of oil due to heating, causing oil leakage to the outside of the foam. If it is less than 30%, the amount of release oil is too small, and Product life cannot be maintained.

Next, the coating layer will be described. As the porous polytetrafluoroethylene used for the coating layer, various types of porous polytetrafluoroethylene which are made porous by operations such as sintering, extraction, foaming, and stretching can be used. Stretched from the viewpoint of is preferred. Further, it is preferable that the porous polytetrafluoroethylene is formed into a fiber by applying a shearing force by an operation such as extrusion, rolling, kneading, or stretching. The porosity of the stretched porous polytetrafluoroethylene membrane is 20 to 98%, preferably 5 to 98%.
0 to 90%, and the average pore size is 0.05 to 15 μm, preferably 0.1 to 2 μm.

The coating layer of the present invention has a function of controlling oil permeation. The control of the amount of oil permeation by the coating layer consisting of only the expanded porous polytetrafluoroethylene film is performed by controlling the film thickness of the expanded porous polytetrafluoroethylene film,
It can be performed by changing at least one of the pore diameter and the porosity.

In the present invention, oil permeation characteristics, abrasion resistance,
In order to further improve shape stability, heat resistance, etc., instead of using a film of stretched porous polytetrafluoroethylene alone as a coating layer, a composite of porous polytetrafluoroethylene and silicone rubber or a porous rubber is used. A membrane composed of a composite of porous polytetrafluoroethylene and a mixture of silicone rubber and release oil can be used.
As the silicone rubber used here, the same RTV (room temperature curing type), LTV (low temperature curing type), HTV
(Heat-curing type) and UV-curing type silicone rubber are most suitable.

As the release oil, silicone oil, especially dimethyl silicone oil, is often used. When a mixture of silicone rubber and a release oil is contained, the mixing ratio of the silicone oil and the release oil is set according to the target oil permeation amount, but the content of the release oil should be less than 2:98. Is preferred. If the content of the release oil is larger than this, it will not be contained in the silicone rubber completely and will be in an ungelled state, making it difficult to control oil permeation.

In this case, the composite method is to impregnate an uncured silicone rubber or a mixture of a release oil and an uncured silicone rubber into a stretched porous polytetrafluoroethylene membrane, and then cure the impregnated porous rubber. A method in which polytetrafluoroethylene and uncured silicone rubber, or polytetrafluoroethylene, release oil and uncured silicone rubber are mixed at an appropriate ratio, and then formed into a sheet by an ordinary method can be used. The content of the silicone rubber or the mixture of the silicone rubber and the release oil can be appropriately determined when the rate of filling the pores is within 100%. In this case, the content ratio of the release oil in the mixture of the silicone rubber and the release oil in the coating layer is smaller than the content ratio of the release oil in the mixture of the silicone rubber and the release oil in the elastic layer. Set to. If the content ratio of the release oil in the coating layer is larger than that of the elastic layer, the transfer of the release oil contained in the elastic layer to the coating layer is inhibited, which is not preferable. In the present invention, in order to impart thermal conductivity and other properties, carbon black, graphite, boron nitride, in a mixture to be composited with the expanded porous polytetrafluoroethylene porous film,
Powders such as alumina and silica may be mixed.

The amount of the release oil supplied to the surface of the fixing roll is changed by changing at least one of the film thickness, pore diameter and porosity of the stretched porous polytetrafluoroethylene film, or by adjusting the content of silicone rubber. It can be changed (when the release oil is not contained in the coating layer), by changing the content of the silicone rubber and the release oil, by changing the mixing ratio of the silicone rubber and the release oil, or by combining these. it can.

In the present invention, the thickness of the coating layer is 3 to 100.
It is set in the range of 0 μm. If the thickness is more than 1000 μm, there is a problem that the elastic layer serving as a base cannot sufficiently exhibit flexibility, and if the thickness is less than 3 μm, durability becomes insufficient.

As a method of providing the coating layer on the surface of the elastic layer, for example, (i) a method of thermocompression bonding with a fluorine resin such as FEP interposed therebetween, and (ii) a method of bonding both with a thermosetting adhesive A method of bonding, (iii) a method of bonding the two with a primer, (iv) a method of bonding the silicone rubber constituting the elastic layer and the silicone rubber in the coating layer at the interface between the two, and the like can be used. it can. When silicone rubber is contained on both the elastic body side and the coating layer side, it is preferable to use the above method (iv) since the joint becomes an anchor-like one and a stronger joint is obtained.

The fixing elastic roll of the present invention has the following configuration, and therefore has the following advantages. The fixing elastic roll has an original function of the fixing roll, and also has a function of supplying a release oil to the roll surface. According to this function, it is possible to supply the release oil through the thick porous tissue material, and to stably supply an appropriate amount of oil to the roll surface for a long period of time while controlling the permeation amount by the coating layer. . Therefore,
Since it is not necessary to separately provide an oil application roll, it is possible to reduce costs and reduce the size of the apparatus by reducing the number of parts related to the fixing unit. In addition, since the porous structure of the thick porous tissue material is filled with a crosslinked silicone rubber containing a release oil, an interconnected cell structure with a high porosity having a fine mechanism of an appropriate pore size is formed. In addition, appropriate elasticity, sufficient restoring force, and sufficient shape stability can be obtained, a change in the shape of the member due to long-term use can be avoided, and a longer life can be achieved to meet recent demands. In addition, since silicone rubber has excellent wettability to release oil and excellent release oil resistance, a sufficiently large oil retaining force can be obtained. As for the heat resistance, a thick porous tissue material in which a silicone rubber foam, a thermosetting resin foam or a polymer foam skeleton surface is coated with a heat-resistant resin is used. Stretched porous polytetrafluoroethylene,
Expanded porous polytetrafluoroethylene and complex with the silicone rubber, or together with the fact that using the expanded porous polytetrafluoroethylene and the release oil and complex with the silicone rubber, may correspond to the recent request 23
High heat resistance of about 0 ° C. or slightly higher than that can be obtained. In addition, since the elastic layer is made of a foam having a soft structure, the roll has appropriate flexibility as a whole, and the nip width can be increased, and printing can be performed on an envelope having a difference in thickness. Also, even in the case where printing is performed, wrinkles do not occur, and good printing or printing can be performed. In addition, since the stress applied to the roll is reduced or absorbed by the soft structure, the life can be further extended. Further, when the silicone rubber contained in the elastic layer and the silicone rubber in the coating layer are bonded and firmly bonded at the interface between the coating layer and the elastic layer, the interface is extremely excellent. And a longer life can be realized.

According to the present invention, a reinforcing layer made of a mixture of release oil and silicone rubber may be provided on the coating layer side inside the elastic layer. This makes it possible to maintain a stable oil supply for a longer period. This is because the material constituting the reinforcing layer is the same or similar to the material existing in the upper and lower layers of the reinforcing layer as the silicone rubber and the release oil. This is because the interface between the coating layer and the elastic layer is reinforced without impeding the transfer of the release oil existing in the impregnated state or crosslinked state to the coating layer. In addition, the reinforcing layer is suitable for both the elastic layer and the coating layer, and effectively reinforces the elastic layer, so that the elasticity and strength of the entire member can be easily adjusted to a suitable level. As a method of providing the reinforcing layer, for example, a method in which a mixture of silicone rubber and a release oil at an appropriate ratio is injected from the lateral direction of the elastic layer, and then subjected to distribution by applying centrifugal force, and then heated. Etc. can be used. The thickness of the reinforcing layer is 5 to 50% of the total thickness of the elastic body layer, more preferably 1 to 50%.
0 to 30%. If it is less than 5%, the effect of the reinforcing layer is not sufficient, and if it exceeds 50%, the resistance of the release oil held in the elastic layer to the outside becomes too large, and the advantages of the sponge roll can be exhibited. Not so good.
The ratio of the release oil to the silicone rubber constituting the reinforcing layer is such that the release oil impregnated in the reinforcing layer is larger than the ratio of the release oil and the silicone rubber combined with the coating layer, and It is necessary that the ratio of the release oil to the silicone rubber in the mixture of the release oil and the silicone rubber, which is cross-linked to the void structure of the elastic layer, is smaller in the layer. If the release oil impregnated in the reinforcing layer is smaller than the ratio of the release oil and silicone rubber compounded in the coating layer, the release that exists in a state of being cross-linked to the void structure of the lower elastic layer is provided. Inhibits the transfer of oil to the coating layer. If the release oil component in the reinforcing layer is larger than the ratio of the release oil to the silicone rubber in the mixture of the release oil and the silicone rubber cross-linked to the void structure of the elastic layer, the reinforcing effect becomes poor.

[0028]

As described above in detail, according to the present invention, the coating layer is excellent in releasability, flexibility and oil swelling resistance, hardly peels off the coating layer, and has high heat resistance and high heat resistance as described above. It is possible to provide a fixing elastic roll that can sufficiently cope with a demand for longer life. Further, since the fixing elastic roll of the present invention has a function of stably supplying an appropriate amount of release oil to the roll surface over a long period of time,
There is no need to provide an oil application roll, and the cost and the size of the apparatus can be reduced by reducing the number of parts related to the fixing unit.

[0029]

Next, embodiments of the present invention will be described. Example 1 As shown in FIG. 1, an 8 mm diameter iron core 2 was added to a silicone rubber foam 1 having an outer diameter of 30 mm, an inner diameter of 8 mm, and a density of 330 kg / cm ³ manufactured by a known method.
To obtain a silicone rubber foam roll. The rubber hardness of this foam roll was 28 degrees. Next, a thermosetting adhesive 3 having a 0.5 mmφ dot-like gravure coating on the back surface side of the stretched porous polytetrafluoroethylene fired film 4 having a film thickness of 20 μm, a porosity of 90%, and a maximum pore diameter of 2 μm was prepared. One turn was wound around the roll surface in a laver winding shape, and then heat-sealed to obtain a laminated roll. Separately from the above, 1 part by weight of silicone rubber (trade name "KE-106" (manufactured by Shin-Etsu Chemical Co., Ltd.)) is added to silicone oil (trade name "KF-96" (Shin-Etsu Chemical Co., Ltd.)
The mixture 5 was prepared at a ratio of 9 parts by weight, and the mixture 5 was poured from the lateral side of the silicone rubber foam portion of the laminating roll, and then distributed by applying a centrifugal force. The mixture of silicone rubber and silicone oil was crosslinked by heating for 80 minutes to obtain a fixing elastic roll 6 having an oil supply function. The outer diameter of the elastic roll was 30 mm, and the rubber hardness thereof was 30 degrees. The above-prepared elastic roll was placed in a fixing device as shown in FIG. 2 and pressed under a constant pressure, whereby good releasability and durability were obtained. No trouble occurred, and no abnormalities such as tears were observed on the surface of the roll after the test. In addition, no deterioration due to swelling due to the release oil was observed. Furthermore, when a copy test was performed using an envelope-shaped recording medium having a matching portion having a thickness difference of 120 μm, no wrinkles or the like were generated, and a good copy image was obtained. In FIG. 2, reference numeral 8 denotes a heat fixing roll, 9 denotes a cleaning roll, 10 denotes a peeling claw, 11 denotes a recording medium, and 12 denotes unfixed toner.

Example 2 As shown in FIG. 3, an melamine resin foam 21 having an outer diameter of 30 mm, an inner diameter of 8 mm, and a density of 1100 kg / cm ³ manufactured by a known method was added to an 8 mm diameter iron. The core 22 was inserted and fused to obtain a melamine resin foam roll. The rubber hardness of this foam roll was 8 degrees. Next, a thermosetting adhesive 23 having a thickness of 20 μm, a porosity of 90%, and a maximum pore diameter of 2 μm on the back side of a fired porous polytetrafluoroethylene fired film 24 gravure-coated with 0.5 mmφ in a dot-like manner, Nori roll on the roll surface
After winding for the number of revolutions, the resultant was thermally fused to obtain a laminated roll.
Separately from the above, silicone rubber (trade name "KE-106")
8 parts by weight of silicone oil (trade name “KF-96” (Shin-Etsu Chemical Co., Ltd.) (Shin-Etsu Chemical Co., Ltd.)
A) 25 was prepared by mixing at a ratio of 2 parts by weight, and this was applied and impregnated on the stretched porous polytetrafluoroethylene fired film 24 on the surface of the laminating roll, and the excess was scraped off. The mixture of silicone rubber and silicone oil was crosslinked by heating for 40 minutes to obtain a laminated roll having a coating layer having an oil permeation control function. Further, a mixture 26 prepared by mixing 7 parts by weight of the silicone oil with 3 parts by weight of the silicone rubber is prepared, and this is injected from the lateral direction of the melamine resin foam 21 of the laminating roll. And then heated at 150 ° C. for 80 minutes to obtain a laminated roll having a 1.5 mm thick reinforcing layer made of a mixture of silicone rubber and silicone rubber as a lower layer in contact with a coating layer having an oil permeation control function. . Further, separately from the above, a mixture 27 of 1 part by weight of the silicone rubber and 9 parts by weight of the silicone oil was prepared, and this was injected from the lateral direction of the melamine resin foam 21 of the lamination roll. , By applying centrifugal force to distribute, then 1
The mixture was heated at 50 ° C. for 80 minutes to crosslink the mixture of the silicone rubber and the silicone oil, thereby obtaining a fixing elastic roll 28 having an oil supply function. The outer diameter of the elastic roll is 3
At 0 mm, the rubber hardness was 20 degrees. The above-prepared elastic roll was placed in a fixing device as shown in FIG. 2 and pressed under a constant pressure, whereby good releasability and durability were obtained. No trouble occurred, and no abnormalities such as tears were observed on the surface of the roll after the test. Also,
No deterioration due to swelling due to the release oil was observed. Furthermore, when a copy test was performed using an envelope-shaped recording medium having a matching portion having a thickness difference of 120 μm, no wrinkles or the like were generated, and a good copy image was obtained.

Example 3 As shown in FIG. 4, the surface of a polyester urethane foam skeleton having an outer diameter of 30 mm, an inner diameter of 8 mm, and a density of 220 kg / cm ³ manufactured by a known method is coated with silicone rubber. An iron core 32 having a diameter of 8 mm was inserted into and fused to the foam 31 thus obtained to obtain a silicone rubber-coated foam roll. The rubber hardness of this foam roll was 13 degrees. On the roll surface, a primer for silicone rubber (trade name "Primer C" (Shin-Etsu Chemical Co., Ltd.))
After spraying and air-drying 33, a film thickness of 20 μm and a porosity of 90
%, A fired porous polytetrafluoroethylene membrane 34 having a maximum pore diameter of 2 μm
It was wound for the rotation. Next, silicone rubber (trade name "K
E-106 "(manufactured by Shin-Etsu Chemical Co., Ltd.) was mixed with 5 parts by weight of toluene (special grade, manufactured by Wako Pure Chemical Industries, Ltd.) at a ratio of 5 parts by weight. After coating from the surface of the ethylene fired film 34, the porous film was impregnated into the voids, and the excess silicone rubber on the surface was scraped off with a brush plate, air-dried at room temperature for 2 hours, and then heated to 100 ° C.
Heat treatment for 1 hour in a constant temperature bath to remove the toluene content in the voids, complete the curing of the silicone rubber, and impregnate the voids of the expanded porous polytetrafluoroethylene with 50% by weight of the silicone rubber. A composite laminated roll having a surface layer having a thickness of 40 μm was obtained. Separately from the above, silicone oil (trade name "KF-96" (manufactured by Shin-Etsu Chemical Co., Ltd.)) is added to 1 part by weight of the silicone rubber.
A mixture 35 was prepared at a ratio of 9 parts by weight, and the mixture was poured from the side of the silicone rubber-coated foam portion of the above-mentioned laminating roll, distributed by applying a centrifugal force, and then heated at 150 ° C. for 80 minutes. The mixture of silicone rubber and silicone oil was crosslinked to obtain a fixing elastic roll 36 having an oil supply function. The elastic roll had an outer diameter of 30 mm and a rubber hardness of 15 degrees. The above-prepared elastic roll was placed in a fixing device as shown in FIG. 2 and pressed under a constant pressure, whereby good releasability and durability were obtained. No trouble occurred, and no abnormalities such as tears were observed on the surface of the roll after the test. In addition, no deterioration due to swelling due to the release oil was observed. Furthermore, when a copy test was performed using an envelope-shaped recording medium having a matching portion having a thickness difference of 120 μm, no wrinkles or the like were generated, and a good copy image was obtained.

As shown in FIG. 5, an 8 mm diameter iron core 42 is added to a silicone rubber foam 41 having an outer diameter of 30 mm, an inner diameter of 8 mm, and a density of 330 kg / cm ³ manufactured by a known method. Insertion and fusion were performed to obtain a silicone rubber foam roll. The rubber hardness of this foam roll is 28
Degree. Next, a thermosetting adhesive 43 is applied on the back side of the fired porous polytetrafluoroethylene film 44 having a thickness of 20 μm, a porosity of 90%, and a maximum pore diameter of 2 μm by 0.5 mmφ.
The gravure coat was wound around the roll surface for one turn in the form of a laver, and then heat-sealed to obtain a fixing elastic roll 45 having no oil supply function.
The elastic roll has an outer diameter of 30 mm and a rubber hardness of 28.
Degree. The above-prepared elastic roll was placed in a fixing device as shown in FIG.
At the time of 10,000 copies, adhesion of toner to the surface of the roll was confirmed, and at the time of 40,000 copies, the recording medium (copy paper) wrapped around the roll occurred. And durability could not be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a structure of an elastic roll according to a first embodiment.

FIG. 2 is a cross-sectional view schematically showing a structure of a fixing device used for evaluating elastic rolls of Examples and Comparative Examples.

FIG. 3 is a cross-sectional view illustrating a structure of an elastic roll according to a second embodiment.

FIG. 4 is a cross-sectional view illustrating a structure of an elastic roll according to a third embodiment.

FIG. 5 is a cross-sectional view illustrating a structure of an elastic roll of a comparative example.

[Explanation of symbols]

1, 21, 31 Foam 2, 22, 32 Iron core 3, 23 Thermosetting adhesive 4, 24, 34 Stretched porous polytetrafluoroethylene fired film 5, 25, 26, 27, 35 Silicone rubber and silicone oil 6, 28, 36 Elastic fixing roll having oil supply function 8 Heating fixing roll 9 Cleaning roll 10 Peeling claw 11 Recording medium 12 Unfixed toner 33 Primer for silicone rubber

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-118871 (JP, A) JP-A-3-204672 (JP, A) JP-A-58-17129 (JP, A) 159459 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 15/20 103 G03G 15/20 104

Claims (3)

(57) [Claims] 1. A fixing elastic roll in which a coating layer having releasability is provided on a surface of an elastic layer made of a thick porous tissue material, wherein the thick porous tissue material is made of silicone rubber.
Foam, thermosetting resin foam, or polymer foam skeleton table
A cross-linked silicone rubber containing a release oil is filled into the pore structure of the thick porous tissue material, which is made of an open-cell foam having a surface coated with a heat-resistant resin. coating layer is porous expanded polytetrafluoroethylene, characterized by comprising the expanded porous polytetrafluoroethylene and complex with the silicone rubber, or expanded porous polytetrafluoroethylene and the release oil and complex with the silicone rubber An elastic roll for fixing having an oil supply function. 2. The thick porous tissue material has a thickness of 5 to 30 m.
2. A fixing device having an oil supply function according to claim 1, wherein
For elastic rolls. 3. A crosslinked silicone containing the release oil.
The filling amount of rubber in the thick porous tissue material is large
Claim that the amount occupies 30 to 90% of the pores of the porous tissue material.
Item 3. An elasticity for fixing having an oil supply function according to item 1 or 2.
roll.