JP2975307B2 - Pressure roller and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure roller in a fixing section of an electronic copying machine or a laser beam printer (hereinafter abbreviated as LBP) and a method of manufacturing the pressure roller.

[0002]

2. Description of the Related Art Conventionally, in order to improve the releasability of toner as a pressing roller in a fixing section of an electronic copying machine or an LBP,
2. Description of the Related Art A roller in which a fluorocarbon resin sleeve is coated on the outer periphery of a rubber roller containing a cored bar is known. This type of conventional roller fixes both ends of a fluororesin sleeve having an outer diameter smaller than the inner diameter of the cylindrical mold loaded inside the inner peripheral surface of the cylindrical mold to side molds for holding a cored bar. In this state, rubber material is injected and filled at high pressure into the annular space between the cored bar and the sleeve, and while the sleeve is expanded with the filling pressure, the sleeve is brought into close contact with the inner peripheral surface of the cylindrical mold, and the sleeve is integrated with the rubber material. (See Japanese Patent Publication No. 50-7097 and Japanese Patent Publication No. 51-27276).

[0003]

In recent years, as the copying machine and the LBP have been designed to be compact and the diameter of the pressure roller in the fixing section has become smaller, the hardness of the silicone rubber layer has been reduced. And, in the conventional pressure roller, especially the thickness is
The thin fluororesin sleeve having a thickness of 0.1 mm or less has a drawback that wrinkles are likely to be formed in the axial direction, and in some cases, the pressure roller cannot be supplied stably.

Japanese Patent Application Laid-Open No. 7-334024 can be exemplified as a conventional example of a measure against the wrinkling of the fluororesin. The above publication discloses that the elastic layer of the pressure roller has a specific gravity of 1.20 to 1.40 and a rebound resilience of 20 to 55%.
A pressure roller made of silicone rubber is disclosed. Toko filtrate is wrinkles even application of the composition of the defined specific gravity resilience modulus as in publication silicone rubber may occur. The above-mentioned publication points out that the wrinkles are caused by repeated use over a long period of time, and the cause is repeated thermal expansion and thermal contraction.

By the way, regarding the silicone rubber used as the elastic layer of the pressure roller, the specific gravity of polyorganosiloxane which is the base gum of the silicone rubber is as follows.
0.98, and the specific gravity of the final composition is satisfied by adding various fillers to this base gum.By adding a filler having a low specific gravity, the specific gravity of the composition is light, and conversely, the specific gravity is heavy. The addition of the filler increases the specific gravity of the composition, and it is not considered that this is a parameter directly related to the function and workability of the pressure roller.

A low-hardness composition has a low stress, so that the surface layer is greatly deformed at the time of thermal expansion. However, it is considered that the higher the rebound resilience, the easier the shape is to be maintained and the less wrinkles are formed. The rebound resilience tends to decrease as the filling rate of the filler increases, and a highly filled composition, that is, a composition having a high specific gravity, tends to have a low rebound resilience.

As described above, since wrinkles are caused by repeated thermal expansion and contraction,
In order to prevent wrinkles, regulating the specific gravity of the rubber composition used for the elastic body is not effective.Rather, regulating the thermal shrinkage of rubber should be more effective. It is considered that by making the size smaller, the elastic layer of the roller becomes less susceptible to thermal expansion and contraction, so that wrinkles generated in PFA (copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether) on the surface layer can be avoided.

The present invention has been made in view of the above points, and has a pressure roller excellent in adhesion between a fluorine resin sleeve and silicone rubber, and a pressure roller capable of efficiently manufacturing the pressure roller. An object of the present invention is to provide a method for manufacturing a roller.

[0009]

In order to achieve the above-mentioned object, the present inventors have manufactured a pressure roller excellent in the reliability of adhesion between a fluororesin sleeve and rubber, and efficiently manufactured this pressure roller. As a result of diligent research to obtain a method of manufacturing a pressure roller capable of producing a pressure roller, there is a correlation between the linear shrinkage of the silicone rubber used for the elastic layer and the wrinkles generated on the fluororesin sleeve of the surface layer. It has been found that wrinkles generated on the surface layer of the pressure roller can be avoided by using a silicone rubber having a ratio of 2.0% or less, and the present invention has been completed.

More specifically, the pressure roller according to the present invention is a pressure roller in which a fluororesin sleeve having a thickness of 0.1 mm or less is coated on the outer circumference of a silicone rubber layer having a hardness of 30 degrees or less, which is coated on the circumference of a cored bar. The present invention is characterized in that a silicone rubber having a linear shrinkage of 2.0% or less is used as the silicone rubber layer, and the manufacturing method is such that metallic sodium is contained in liquid ammonia on the inner surface of a fluororesin sleeve having a thickness of 0.1 mm or less. After performing a surface treatment using a dissolving treatment solution or a treatment solution in which naphthalene and metallic sodium are dissolved in an organic solvent, an adhesive treatment is performed using an adhesive, and the fluororesin sleeve that has been subjected to the adhesion treatment is treated. After fixing both ends to a side mold holding a core metal that has been subjected to an adhesive treatment in advance using an adhesive, this is held in a cylindrical mold, and placed in an annular space between the core metal and the sleeve. The shrinkage is 2.0% or less silicone rubber is injected, is to its characterized in that the heating vulcanization to integrate the silicone rubber the fluororesin sleeve.

More specifically, the cause of the wrinkles is that, after the roller formed by heat molding at the time of forming the roller is cooled to room temperature, the secondary vulcanization is usually carried out at a temperature of about 200 ° C. As a result, the roller undergoes thermal expansion and contraction due to repeated heating and cooling, and PFA on the surface layer is plastically deformed.Since the PFA layer and the silicone rubber layer are bonded, the rubber contracts at the bonding surface. It is considered that it was not possible to do so and abnormal contraction in the 90 ° direction caused wrinkles in the PFA layer.

As described above, since wrinkles are caused by repeated thermal expansion and contraction,
In order to prevent wrinkles, simply regulating the specific gravity of the rubber composition used as the elastic body is not effective.It is considered that it is more effective to regulate the heat shrinkage of the rubber. It is considered that by making the roller smaller, the elastic layer of the roller is less susceptible to thermal expansion and contraction, so that wrinkles generated in PFA on the surface layer can be avoided.

As a test method for measuring the degree of the thermal shrinkage, a linear shrinkage rate test is specified in JIS C 2123.
The linear shrinkage in the present invention is measured according to JIS C 2123 described above. In the present invention, for example, in the case of addition type silicone rubber, the compound has a depth of 2 mm,
Place it in a 130 × 130 mm mold at room temperature.
After vulcanizing for 10 minutes at a pressure of about 30 kg / cm ² in a press preheated to 0 ° C. (this 10 minutes is the time after the mold reached 120 ° C.), it is allowed to cool to room temperature, and 200 in constant temperature bath
After secondary vulcanization at 4 ° C for 4 hours, allow it to cool to room temperature, measure the two lengths connecting the midpoints of the opposing sides with a vernier caliper to a reading of 0.1 mm, and average the average value after vulcanization. The length of one side of the test piece was used, and the linear shrinkage was measured by the following equation.

[0014]

(Equation 1)

Generally, important factors for determining the shrinkage of rubber include vulcanization temperature, vulcanization system, and free volume fraction in rubber. First, regarding the effect of vulcanization temperature,
Generally, the higher the vulcanization temperature (molding temperature), the linearly the linear shrinkage increases. Further, under the influence of the vulcanization system, the crosslinked chain length of the polymer is short, and the compact structure is less likely to shrink. This means that the addition-type silicone rubber is unlikely to shrink between the peroxide-curable millable silicone rubber and the addition-type vulcanization liquid silicone rubber. The reason will be described below.

In a peroxide-cured silicone rubber, an organic peroxide such as 2,5-dimethyl-2,5-di (t-butylperoxy) -hexane is used as a vulcanizing agent. In general, it is molded at a high temperature of about 160 to 210 ° C. On the other hand, addition-type silicone rubber has a high vulcanization rate and is usually molded at a temperature of about 90 to 140 ° C, and can be molded at a temperature about 70 ° C lower than that of a peroxide-cured silicone rubber. From the viewpoint, it can be said that the addition type silicone rubber is less likely to shrink.

Further, the polymer used for the silicone rubber is mostly dimethylpolysiloxane, the average degree of polymerization of which is 100 to 1,000 in the case of the liquid type used for the addition type silicone rubber, and the addition of peroxide. 6,000 to 1 for millable type used for vulcanized silicone rubber
Since it is a linear polymer of about 0,000, it can be said that the addition type silicone rubber is harder to shrink even from the viewpoint of molecular structure.

Further, the free volume is substantially
Because it depends on the organic material portion of the rubber composition, increasing the amount of the inorganic filler will reduce shrinkage. From this fact, the linear shrinkage ratio of rubber having the same molding temperature and vulcanization system is practically determined by the amount of filler. Therefore, by forming the pressure roller of the present invention in accordance with the method of manufacturing the pressure roller of the present invention, wrinkles do not occur in the surface layer of the fluororesin during the manufacture of the pressure roller, and the durability is excellent. A pressure roller can be obtained.

[0019]

The pressure roller according to the present invention has a linear contraction rate as a silicone rubber layer having a hardness of 30 degrees or less coated on the outer periphery of the cored bar.
Use 2.0% or less of silicone rubber
By covering with a fluororesin sleeve of 0.1 mm or less, the thermal shrinkage of the silicone rubber can be reduced, so that the silicone rubber is less susceptible to thermal expansion and shrinkage. The adhesiveness of the fluororesin sleeve to be performed is improved, and wrinkles generated in the fluororesin sleeve can be eliminated.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described. In FIG. 1, reference numeral 1 denotes a pressing roller, and the pressing roller 1 has a cored bar 2 covered with an elastic layer 3 around its outer periphery.
Further, the outer periphery thereof is covered with a fluororesin sleeve 4. In the present invention, the elastic layer is made of a silicone rubber having a heat shrinkage of 2.0% or less.

In the present invention, the rubber hardness of the elastic layer 3 made of silicone rubber is not particularly limited as long as it is 30 degrees or less according to JIS A (JISK6301), but it can be selected arbitrarily. Since rubber has a low stress and tends to wrinkle easily, it is preferable to apply a low hardness of 20 degrees or less. As the base polyorganosiloxane containing a vinyl group, methylvinylpolysiloxane is generally used, but methylphenylvinylpolysiloxane and the like can also be used.

In the present invention, the formulation of the filler for the elastic layer 3 is particularly important. Generally, silicone rubber is a base.
A reinforcing filler and an extending filler are added to the polyorganosiloxane. As the reinforcing filler, wet silica or dry silica (fumed silica) is generally used. Here, the wet silica refers to a reinforcing silica made of silicon oxide (SiO ₂ ). As a production method, a direct method of directly decomposing sodium silicate with sulfuric acid or a method of reacting sodium silicate with salts. There are various methods such as an indirect method in which an acid salt is formed and then decomposed with sulfuric acid or carbon dioxide gas. Typical wet silicas include NipsilVN3 (trade name, manufactured by Nippon Silica Industry Co., Ltd.), Carplex CS-5 (trade name, manufactured by Shionogi Pharmaceutical Co., Ltd.), Starsil S (trade name, manufactured by Kamijima Chemical Industry Co., Ltd.), Toksil US (Trade name of Tokuyama Corporation), Shilton R-2 (trade name of Mizusawa Chemical Industry Co., Ltd.), Hisil 223 (trade name of PPG (USA)), Ultras
il VN3 (brand name from Degussa GmbH, Germany), Vulkasil S
(Trade name, manufactured by Bayer AG (Germany)), and a grade having an average particle size of 30 μm or less, preferably 5 μm or less is used.

The fumed silica is composed of silicon dioxide produced by a thermal decomposition method of silicon halide, a heat reduction of silica sand, and an air oxidation method of vaporized SiO ₂ or a thermal decomposition method of an organic silicon compound. Aerosil 20 with reinforcing silica
0 and Aerosil R 972 (trade name, manufactured by Nippon Aerosil Co., Ltd.), Cab-O-Sil MS-5 (trade name, manufactured by Cabot (USA)),
Reolosil QS 102 (trade name, manufactured by Tokuyama Corporation) and the like are exemplified. In the present invention, if necessary, wet silica and dry silica may be appropriately used in combination, and further,
For the purpose of preventing secondary bonding due to the activity of the silica surface,
A wetting agent (wetter) may be added. Examples of these wetting agents include silicone resins, alkoxysilanes and siloxanes, hydroxysilanes and siloxanes, silazanes, organic acid esters, and polyhydric alcohols. You.

In the present invention, it is important to add a metal oxide filler to the silicone rubber in an amount of 5 to 45 parts by weight, preferably about 15 to 35 parts by weight, in addition to the reinforcing filler. As metal oxides, Celite 270,281,501,503,5
05,535,545,560,577, FC, SSC, Super Floss, Snow Floss
(These are the product names of Johns-Manville (USA)) and radio lights # 100, # 200, # 300, # 500, # 500-S, # 600, # 700, # 80
0, # 800 ー S, # 900, F, SPF, Fine flow F, Fine flow
B (the above names of Showa Chemical Industry Co., Ltd.), diatomaceous earth (silicon oxide), crystallite AA, VX-S, VX-S-2, V
X-SR (Trade name made by Tatsumori Co., Ltd.) and Min-U-Sil 5,1
Quartz powder (silicon oxide) such as 0,15,30 (the above trade names made by USSilica (USA)), R-310, A-110, A-SP (the above trade names made by Sakai Chemical Industry Co., Ltd.) Titanium oxide, zinc flower 1
Oxide (trade name manufactured by Sakai Chemical Industry Co., Ltd.), Bayferrox 130M (trade name manufactured by Bayer (Germany))
Diiron trioxide (Bengara), triiron tetroxide (iron black) such as OBR-20 (trade name, manufactured by Nippon Begara Kogyo Co., Ltd.), chromium oxide G5, G7, green S (Nippon Chemical Industry Chromium oxide, such as the product name of ALCO, AL-45, AL-43M, AL-30, AL-
Examples thereof include aluminum oxide (alumina) such as 43PC (trade name, manufactured by Showa Denko KK). In the present invention, at least one filler composed of these metal oxides is used.
More than one kind needs to be added to silicone rubber.

The fillers other than the metal oxide fillers include, for example, novacurite (siliceous sandstone), zirconium silicate, clay (aluminum silicate), talc (hydrated magnesium silicate), wollastonite. (Calcium metasilicate), aluminum sulfate,
Barium sulfate, lithopone, molybdenum disulfide, mica (mica powder), graphite or the like may be used as appropriate, or may be used in combination with a metal oxide filler.

Further, in LBP, a negatively charged toner is generally used, and PFA or silicone rubber used for the pressure roller is a negatively charged substance, so that an electrostatic offset easily occurs. Tier 3
May be given conductivity. In the present invention,
By adding at least one kind of conductivity-imparting agent as a silicone rubber filler, the volume resistivity can be increased by 10 ¹⁰
Ω · cm or less. Examples of the conductivity-imparting agent include acetylene black such as Denka Black (trade name, manufactured by Denki Kagaku Kogyo KK) and Toka Black # 5500, # 4500.
Metal powders such as conductive carbon black, graphite, silver, copper, nickel, etc., such as (trade name of Tokai Carbon Co., Ltd.) and Ketjen Black EC (trade name of AKZO (Netherlands)), conductive zinc flower NO.1 , NO.2 (product name of Honjo Chemical Co., Ltd.) and 23-K (product name of Hakusui Chemical Co., Ltd.)
Conductive barium sulfate such as Pastran 4110 (trade name of Mitsui Kinzoku Co., Ltd.), conductive titanium oxide such as W-1 (trade name of Mitsubishi Materials Corporation),
Examples include antistatic calcium carbonate and carbon fiber such as EC-1, EC-5 (trade name of Maruo Calcium Co., Ltd.), but carbon black such as acetylene black and Ketjen black is generally used. .

In the present invention, a heat-resistant agent such as cerium oxide may of course be added. Further, usually, a pressure roller made of silicone rubber is often supplied in a colored state in a reddish color, and in this case, a reddish color is generally used as a coloring agent. As the type of the above-mentioned bengara, a bengara for rubber prescribed in SRIS 1108 (Japanese Rubber Association Standard) can be applied, and when it is necessary to pay attention to the orientation in the rubber at the time of processing, the biferrox 130 is used. A spherical grade having an average particle size of 0.3 μm or less, such as M (trade name, manufactured by Bayer AG, Germany) may be added in an amount of about 0.2 to 2% by weight based on silicone rubber. Recently, CP-2 has been considered in consideration of dispersibility and scattering prevention.
In many cases, about 0.3 to 4% by weight of a silicone masterbatch having a content of about 50%, such as 1 (a product name of Dow Corning Toray Silicone Co., Ltd.) is added.

As the vulcanizing agent in the present invention, in the case of a millable silicone rubber, ordinary organic peroxides for silicone rubber can be used, and benzoyl peroxide, bis 2,4-dichlorobenzoyl peroxide, Mild peroxide, di-tert-butyl peroxide, tert-butyl perbenzoate, paramonochlorobenzoyl peroxide, 2,5-dimethyl-2,5-DG (tert-butyl peroxy) -hexane, tert-butyl cumyl peroxide, tertiary Butylperoxy-2-ethylhexanoate, tert-butylperoxyisopropyl carbonate, 1,3-bis (tert-butylperoxy)
-3,3,5-trimethylcyclohexane, tertiary butylperoxy 3,5,5-hexanoate, etc., are exemplified by dicumyl peroxide or 2,5-dimethyl
The use of 2,5-G (tert-butylperoxy) -hexane is common.

However, in the present invention, a millable type using the above-mentioned organic peroxide as a vulcanizing agent is not used.
In the presence of a platinum catalyst, an addition-type liquid silicone rubber comprising a vinyl group-containing polysiloxane and a hydropolysiloxane is more advantageous than a millable type in terms of the fact that it is easier to obtain a composition having a lower hardness and the aforementioned linear shrinkage. is there.

As a material of the fluororesin sleeve used in the present invention, PFA having a thickness of 0.1 mm or less is generally used.
If necessary, a conductivity-imparting agent such as the above-described conductive carbon black may be added to this PFA to increase the volume resistivity to 10%.
^A pressure roller may be formed by forming a conductive PFA of ¹³ Ω · cm or less and covering the outer periphery of the elastic layer.

In the present invention, the adhesion between the fluororesin sleeve 4 and the silicone rubber 3 serving as the elastic layer is performed by using a treatment solution comprising metallic sodium and liquid ammonia or tetrahydrogen.
Chemlock 607 (Road, etc.) is applied to the inner surface of the fluororesin sleeve 4 that has been internally treated with a treatment solution in which sodium metal and naphthalene are dissolved in THF or ethylene glycol dimethyl ether such as (trade name of Junkosha Co., Ltd.)
Far East Incorporated product name)
Apply a silicone primer such as DY 39-067 (trade name of Dow Corning Silicone Co., Ltd.) and vulcanize it with the elastic layer 3 made of silicone rubber to adhere to the elastic layer 3 and use Can go crazy.

The adhesion between the core 2 and the elastic layer 3 can be coped with by using a silicone primer such as Primer No. 16 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.). At this time, after the surface of the metal core metal 2 is previously activated with sandplast or the like, the surface is degreased with methylene chloride or the like, a primer is applied, and if necessary, calcined at 130 ° C. for about 30 minutes before use. .

[0033]

Next, an embodiment of the pressure roller 1 according to the present invention will be described below, but the present invention is not limited thereto.
The hardness and rebound resilience measured by a JIS A hardness tester, which are the physical property values of the silicone rubbers in Examples and Comparative Examples, are JIS K 63
01, the specific gravity and the linear shrinkage were measured according to JIS C 2123, respectively.

[0034]

[Example 1] This is a typical addition type liquid silicone rubber.
Take 10 kg of A solution of DY35-681A / B (trade name of Dow Corning Silicone Co., Ltd.) in a Hobart mixer,
0.5 kg of Radiolite F (trade name, manufactured by Showa Chemical Industry Co., Ltd.), which had been previously heated at 130 ° C. for 2 hours to remove water as diatomaceous earth, was added and mixed for 2 hours. Next, this composition was placed in a bail can having a capacity of 20 liters, and then defoamed in a vacuum chamber for 16 hours to prepare a solution A used in Example 1. In the same procedure, add 10kg of B solution of DY35-681 to radio light
0.5 kg of F was added to prepare solution B used in Example 1.

Next, a metal shaft having an outer diameter of 10 mm to which an adhesive has been applied in advance and 100 PFA sleeves each having an inner diameter of 25 mm and a wall thickness of 50 μm each having an adhesive applied in advance are prepared, and the metal shaft is placed in a side mold. After holding, insert it into the PFA sleeve, chuck both ends, then 26mm inside diameter, 310mm length
Was mounted together with the shaft at room temperature. next,
The bale can containing the above composition was set in a bale pump, and the liquid A and the liquid B were mixed with a static mixer, and liquid silicone rubber was filled from the rubber injection port of the side mold.

Next, the mold was heated in a hot air oven at 130 ° C. for 1 hour to cure it, and then the pressure roller was detached from the mold. Subsequently, 100 pressure rollers were formed in the same procedure, and the pressure rollers were further heated in a thermostat at 200 ° C. for 4 hours, then taken out of the thermostat, and the occurrence rate of wrinkles of the fluororesin in the surface layer was measured. I asked. In the composition of Example 1, the occurrence rate was 2 out of 100 lines, and the wrinkles generated in the two lines were extremely small. In Example 1, almost no wrinkles occurred.

[0037]

【table 1 】

[0038]

Examples 2 to 13 100 pressure rollers were prepared in the same manner as in Example 1 except that the compositions having the compositions shown in Table 1 were used, and the wrinkle generation rate of the fluororesin in the surface layer was determined. The quartz powder used in Examples 4 to 7 was Crystallite VX-S (trade name, manufactured by Tatsumori Co., Ltd.), and the alumina used in Examples 8 to 10 was alumina.
AL-43PC (Product name of Showa Denko KK)
The zinc oxide used in 13 was Zinc Hua No. 1 (trade name, manufactured by Sakai Chemical Industry Co., Ltd.), and all were heated at 130 ° C. for 2 hours before use to remove moisture contained in the same manner as in Example 1. Used from.

As can be seen from the results in Table 1, Examples 2 to 13
It was found that wrinkles hardly occurred. Examples 1 to 13
The rebound resilience of all compositions is 56% or more, and the linear shrinkage of silicone rubber is 2.0% or less. It turned out that there was no problem. In Example 13, the rubber layer had some foaming.

[0040]

[Comparative Examples 1 to 3] 100 pressure rollers were prepared in the same manner as in Examples 1 to 13 except that the formulations shown in Table 1 were used, and the wrinkle generation rate of the fluororesin in the surface layer was determined. In Comparative Examples 1 to 3, the wrinkle occurrence rate was high, and the wrinkle size was as large as 30 mm or more. From the results shown in Table 1, it was found that when the linear shrinkage was 2.1% or more, wrinkles were formed even at a high rebound resilience.

[0041]

Examples 14 to 21 X-34-290-A / B (trade name, manufactured by Shin-Etsu Chemical Co., Ltd .: volume specific resistance 1 × 10 ⁴ Ω · cm), which is a typical conductive addition type liquid silicone rubber, was used. 100 pressure rollers were prepared in the same manner as in Examples 1 to 14 except that the composition shown in Table 2 was used, and the wrinkle generation rate of the fluororesin in the surface layer was determined.

[0042]

[Table 2]

From the results in Table 2, it can be seen that by setting the linear shrinkage of the silicone rubber to 2.0% or less, the surface PFA layer hardly wrinkles irrespective of the specific gravity and rebound resilience of the composition, which is a practical problem It turned out there was no.

[0044]

Comparative Examples 4 to 11 100 pressure rollers were prepared in the same manner as in Examples 1 to 13 except that the formulations shown in Table 2 were used, and the wrinkle generation rate of the fluororesin in the surface layer was determined. In Comparative Examples 4 to 11, the wrinkle occurrence rate was high, and wrinkles that became a practical problem even when the specific gravity was 1.20 to 1.40 and the rebound resilience was in the range of 20 to 55% as in Comparative Examples 10 to 11 were particularly high. It was found to happen.

[0045]

The pressure roller according to the present invention uses silicone rubber having a linear shrinkage of 2.0% or less for the silicone rubber layer, so that the heat shrinkage of the silicone rubber, which is the elastic layer, can be reduced. Since the silicone rubber is less susceptible to thermal expansion and contraction, the adhesiveness of the fluororesin sleeve coated on the outer periphery is improved, wrinkles generated on the fluororesin sleeve can be avoided, and the pressure roller can be efficiently manufactured. Is what you can do.

[Brief description of the drawings]

FIG. 1 is a sectional view of a pressure roller according to the present invention.

[Explanation of symbols]

 1 Pressure roller 2 Core 3 Silicone rubber layer 4 Fluororesin sleeve

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // B29K 27:12 83:00 105: 24 503: 04 705: 00 B29L 31:32 (58) Fields surveyed (Int.Cl. . ^6, DB name) F16C 13/00 B29C 35/02 B29C 39/10 C09D 183/04 G03G 15/20 B29K 27:12 B29K 83:00 B29K 105: 24 B29K 503: 04 B29K 705: 00 B29L 31:32

Claims (6)

(57) [Claims] 1. A pressure roller in which a fluororesin sleeve having a thickness of 0.1 mm or less is coated on the outer periphery of a silicone rubber layer having a hardness of 30 degrees or less, which is coated on the outer periphery of a cored bar, A pressure roller characterized by using a silicone rubber of 2.0% or less. 2. A silicone rubber is a linear shrinkage of 2.0% or less, and a pressure roller according to claim 1, wherein the modulus of repulsion elasticity is characterized Oh Rukoto in 56% or more. 3. The silicone rubber is added with a filler in an amount of from 5 to 45%.
3. The pressure roller according to claim 1, wherein the pressure roller is contained by weight. 4. The bulking filler is a metal oxide, diatomaceous earth (silicon oxide), quartz powder (silicon oxide), alumina (aluminum oxide), titanium oxide, zinc oxide (zinc oxide),
It contains at least one compounding agent that functions as a filler selected from the group of metal oxides consisting of chromium oxide, red iron oxide (diiron trioxide), and iron black (iron trioxide). The pressure roller according to claim 1, wherein the pressure roller is used. 5. The pressure roller according to claim 1, wherein the silicone rubber is an addition type liquid silicone rubber. 6. A surface treatment on the inner surface of a fluororesin sleeve having a thickness of 0.1 mm or less by using a treatment solution in which metallic sodium is dissolved in liquid ammonia or a treatment solution in which naphthalene and metallic sodium are dissolved in an organic solvent. After performing the bonding process using an adhesive, both ends of the fluororesin sleeve subjected to the bonding process are fixed to a side mold holding a core metal that has been subjected to a bonding process using an adhesive beforehand. This is held in a cylindrical mold, and silicone rubber having a linear shrinkage of 2.0% or less is injected into an annular space between the cored bar and the sleeve, and the mixture is heated and vulcanized to cure the fluororesin sleeve and silicone. A method for manufacturing a pressure roller, wherein rubber and rubber are integrated.