JPH01281479A - Elastic rotor and fixing device - Google Patents

Abstract

PURPOSE:To reduce the offset of toner by providing a 1st elastic layer and a 2nd elastic layer which is formed on the surface of the 1st elastic layer and whose hardness is higher and thickness is thinner than the 1st elastic layer as an elastic layer and making the 2nd elastic layer contain a fluorine surfactant. CONSTITUTION:A pressurizing elastic rotor 1 is produced by forming the elastic layer on the surface of core bar 3 made of stainless steel, etc., and having a specified outside diameter. The elastic layer is provided with the 1st elastic layer 4 formed on the core bar 3 and the 2nd elastic layer 5 formed on the 1st elastic layer 4. The 1st elastic layer 4 is a sponge layer and the 2nd elastic layer is a silicone rubber layer whose hardness is higher and thickness is thinner than those of the sponge layer 4. Thus, the electrostatic charging potential of the elastic rotor is lowered and the offset of the toner can be drastically reduced, then the elastic layer can be appropriately used for the elastic rotor and the fixing device of a printer, etc.

Description

Detailed Description of the Invention Lsu-h (7) Top-Mingyo 1 Unpublished II+ relates to an elastic rotating body used in photocopying devices, printers, and various other image forming devices. In particular, in the image forming apparatus, the sheet-like rolling material V is used as a conveyor roller or heddle for conveying or fixing recording materials, etc., and has low toner offset and wrinkle-free properties. No outbreak 1
One is about a durable elastic rotating body. Therefore, the home use also relates to a fixing device using such an elastic rotating body.

Positive ``L force'' E angle Composite using the conventionally used ``Scroll photo method''! i
-Fixing devices used in devices, printers, etc. are as follows:
21<.

To explain this in detail, in an electrophotographic visualization device, a transfer material such as a transfer paper on which a toner image is formed using the normal 6-way electrophotographic page method is fed to a fixing device, and the transfer material is transferred to a fixing device. The toner image is fixed as a permanent image.

For example, as shown in FIG. 5, the fixing device includes a heat-fixing rotating body, that is, a fixing roller 2, which is in the form of a roll in this example, and an elastic rotating body for pressing, which is in the form of a roll in this example. 1
! Consists of +3 force I pressure roller l,
The fixing roller 2 is made of PTFE (polytetrafluoroethylene), PF, etc. on the surface layer of a hollow core 6 made of aluminum, iron, etc.
Coat with resin 7 such as A (co-topolymer of polytetrafluoroethylene and perfluoroalkoxyethylene) or coat with material #47 with excellent mold release properties such as silicone rubber.
(It is formed by
A heater 8 such as a heater 8 is placed inside the roller, and serves to heat the fixing roller 2. On the other hand, the pressure roller 1 is made of iron, stainless steel, etc.
It is formed by coating a portion of L with silicone rubber, etc., which has good releasability. The fixing roller 2 and the fixing roller 1 are pressed against each other by a pressing stage (14 not shown) such as a spring.

Constant X1JA71 also has a temperature sensor such as a thermistor ^7-12
is provided to detect the surface temperature of the fixing roller 2.

This feeling is S! Element and temperature Jll! The transfer material 15 with the toner image 16, which is fixed by transferring the toner image 16 to the heater via the i circuit (not shown), is fixed by a person (+ guide 14). The toner image 16 on the transfer material 15-1 is placed between the roller 2 and the pressure rollers A and L, and is fixed by applying pressure and pressure between the fixing roller and the pressure roller. The transfer material 15 is guided out of the machine by the guide [7, and the transfer material 15 that has been attached to the fixing row P2 is peeled off by the separation claw 13) m', IIJ
The roller II 2 is provided with a cleaner, i.e., a cleaner 71, 9, which cleans toner and paper dust attached to the surface l- of the roller 2.

The weighted L roller 1 formed the silicone rubber 4 on the surface of the core metal 3 as described above. In addition to the so-called "solid type" type, there is also a so-called "sponge type" in which a multi-fL silicone rubber layer is formed on the surface of the core bar 3, and a thin layer of silicone rubber is further formed on this surface.

&”J1y Lou L, Meng2Yokoj”Lll However,
The solid type roller does not heat up when the constant n property is low temperature 1"4, the heat capacity μ is large, and the fixation performance is poor. Also, as a transfer material → paper folding, t4f, :l ( 60
g/rrr' or less) using g1. In this case, the answer is ``
1. Wrinkles occur. The problem is that it is easy! ] Next, sponge type rollers have an internal structure with a porous elastic layer, and because a large amount of air is present, the thermal conductivity is low, making it difficult to fix in low-temperature environments. The properties were good, and "wrinkles" were unlikely to occur even when thin paper or sealing rods were tested.

However, the sponge type roller has the drawback of increasing the amount of toner set. The reason why this offset occurs is thought to be that the surface of the pressure roller 1 has the same polarity as the toner and repels the toner image on the transfer material 1 toward the fixing roller 2. The same phenomenon occurred with solid type rollers.

Furthermore, due to the structure of a fixing device that uses sponge-type rollers, it is not possible to increase the pressure contact between a pair of rollers compared to a fixing device that uses solid-type rollers, and the toner image on the transfer material is forced onto the transfer material. The adhesion force is weak,
This is because the toner is likely to be offset toward the fixing roller.

According to the results of research experiments conducted by non-users, when a pressure roller made of sponge-type silicone rubber and a fixing roller coated with Teflon resin are used, the frictional charging potential generated between the pair of rollers is When paper is used as a filter, the fixed voltage after passing the paper is +2KV for the fixing roller, -3KV or more for the pressure roller, and when negative toner is used, the voltage is applied to the fixing roller. The occurrence of toner-off upper-2 toners increased to j[A.

Therefore, the object of the invention is to use a sponge-type elastic rotating body, contain a 7-/strand surfactant in at least the elastic layer of the elastic rotating body, and reduce the air resistance for one elastic rotation. An object of the present invention is to provide a fixing device using an elastic rotary body that reduces the charging potential of the body to a low F level and minimizes toner offset.

1 shi! Stop t-go-ri! The above objects are achieved by an elastic rotating body and a fixing device according to the present invention. In other words, the present invention provides a first elastic layer as an elastic layer in an elastic rotating body having at least an elastic layer, and a surface of the first elastic layer having a hardness < ft higher than the first elastic layer. The thickness has been reduced! 7S2, at least the second elastic layer is an elastic rotating body containing a fluorosurfactant, and preferably the first elastic layer is made of porous soricone rubber; The second elastic layer includes), perfluoroalkylpolyoxyethylene ethanol, perfluoroalkylcarbonyl, perfluoroalkylbetaine, perfluoroalkylamine oxide, perfluoroalkylethylene oxide adduct, beveloloa as a thread surfactant. l rekyl phosphate ester, non-dissociable barfluoroalkyl compound, etc. at 0.003 to i. ol'J%. kf t L
< It 0 , 0 1 - 0 , 5 , 1 r
Contains i%. Further, it is preferable that the first elastic layer has toughness.

Furthermore, according to the other six aspects of the invention, a rotary body for fixed stones is formed on the surface of the rotating body for heating and fixing the toner image on the transfer material, and at least an elastic layer is formed on the rotary body for fixing the transfer material. In a fixing device having an Au pressurized tubular bone rotor that is pressed and conveyed by a pressure member, the elastic layer of the pressurizing protective rotor includes a first elastic layer and a surface of the first elastic layer. a second bony layer with a thickness that is one layer thinner;
At least the second elastic layer contains a fluorine-based surfactant.
J-san Salel, also 6ft! , <if.

The first elastic layer of the elastic rotor for Jll J, t, is made of porous silicone rubber and has electrical conductivity, and is electrically conductive. The sexual layer is made of PFA.

Next, with reference to one drawing, an elastic rotating body and a fixing member according to the present invention! A, 21 further 91. <Explain.

In the embodiment shown in FIG. 1, the fixing device using the elastic rotor of the present invention is composed of a pair of rotors: a heat-fixing rotor 2 and an elastic rotor 1 for applying fI. teeth! It is heated by the Xlogen heater 8.

The heat-fixing rotating body 2 and the pressing elastic rotating body 1 can be in the shape of a roll or a belt; however, in this embodiment, the heating-fixing rotating body 2 is a constant n roller, and the elastic rotating body 1 for pressing The rotating body 1 is a pressure roller. 1 Wearing roller 2 is a metal vibro (thickness 0.7 to 2.0 mm) made of cylindrical aluminum or stainless steel with a predetermined outer diameter of 41 and coated with PFA or PTFE on the surface.
(4), J chloride tyrene resin) layer 7 (thickness 50-300 μm
).

A temperature sensing element 12 such as a thermistor for detecting and controlling the surface temperature is installed in contact with the surface of the stone roller 2. There is a small amount of toner on the surface of the fixing roller 2.
A cleaning pad 9 is provided in pressure contact with the surface of the roller to apply a release agent such as a surfactant or to remove offset toner. lc whisper example cleaning bud 9
is heat-resistant felt 10 made of Teflon resin containing a mold release agent.
The frame 1l-CIAI is made of heat-resistant resin.

Pressure roller l is facing towards roller 2.

It is manufactured by forming an elastic layer on the surface of a core metal 3 made of plated iron or stainless steel and having a predetermined outer diameter. According to the first elastic layer, the first elastic layer 4 formed on the core metal 3 and the Ajl first
In this embodiment, the first 9111 layer 4 is a sponge layer, and the second elastic layer has a higher elasticity than the sponge layer 4. , a silicone comb layer with a reduced thickness.

The transfer material 15 is fed from the first guide 14 between the fixing roller 2 and the pressure roller l, and the toner image 16 is transferred to the transfer material 15.
L, is heated and fixed. The fixing roller 2 is equipped with a motor etc. (14
The pressure roller l is driven by a driving means (not shown), and the pressure roller l is
It is driven by the fixing roller 2. Also, a pressure of 4 to 10 kg is applied between the rollers of the light, and the fixing roller is
Heated to 60°C to 190°C.

To explain further, the core metal 3 of the uninvented pressure roller l usually has a diameter of 8 to 14 m from the viewpoint of structure-1-strength.
m or more. Further, the sponge layer 4 forms substantially closed cells, the thickness of the layer is 2-3 mm or more and 20 mm or less, and the rubber hardness of the sponge layer 4 is 20 mm.
~400 (rubber hardness tester ASKARC), and furthermore, the surface of this sponge layer 4 has rubber &j! degree JIS-A 3
0-500 silicone rubber layer 5 (thickness 0.5-2mm
) is formed. The preferred method for manufacturing the sponge rotating body is the method reported in Japanese Unexamined Patent Publication No. 59-618641, which was proposed by a non-applicant, but any other methods can be used.

According to the invention, in the pressure roller I, the second elastic layer, that is, the silicone rubber layer 5, is the first elastic layer.

In other words, the hardness is higher than that of sponge layer 4 [I, and the thickness is Q〈
The second elastic layer 5. That is, if the hardness of the surface layer is low or the thickness is thick, the first elastic layer 4, which is a sponge layer, cannot exhibit the effect of low elasticity within 1 minute. .

Furthermore, according to the invention, the silicone rubber layer 5 of the second elastic layer
A fluorine-based surfactant is added therein, and the fluorine-based surfactant is, for example, EFTOP-EF122B (trade name of a fluorine-based surfactant).

(manufactured by Mitsubishi Metals Co., Ltd.) is preferably used, and 0O03-1
．． 0 weight + 1) %, preferably 0.01 to 0.5 weight % is added. The addition value of the fluorosurfactant added to the silicone rubber layer 5 is 1.0 tons:55 or more,
It depends on the type of surfactant, but which ones cure 31
! It causes harm and becomes energetic. In addition, the addition of a surfactant to the silicone rubber layer 5 is disadvantageous in that if the amount is less than 0.003%, the surfactant will not be oriented on the surface of the silicone rubber layer 5.
Therefore, the elastic rotating body, that is, the pressure roller l in this embodiment
The added fluorine-based surfactant is decomposed within the silicone rubber layer even at high temperatures, causing the surfactant on the surface to evaporate and lose the original friction effect such as lowering the cardiac potential. It has the advantage of being able to maintain its effect for k hours without coming off from the silicone rubber even when heated. / Bafle Orooa I Lekiro I Lekiroxyethyelay Ethanol, Perfulle Oloalkyl Power J -Repon Uglation NP, Burafuru Oloalkyl Animonium Salt, Rumma Rukill Hetai>, Barfulul Oloal Killing Leain Leamin Kizide. There are perfluoroalkyl ethylene adducts, perfluorofurkyl phosphate esters, and non-Ml&perfluoroalkyl compounds T.

The fixing device shown in Fig. 1 will be explained in more detail. Fixing roller 2 has lJ11 diameter of 20 mm and thickness of 1.5 mm.
A PFA layer with a thickness of 1QOgm was formed on the surface of an aluminum metal vibro. In addition, a conductive spring (not shown) was brought into contact with the end face of this vibro to ground the fixing rotor. The pressure roller 1 is made of stainless steel (straight (110)
A sponge P: Ij4 (rubber hardness 30°, thickness 4 mm) made of porous silicone rubber is formed on the core metal shaft 3h (mm), and a silicone rubber layer 5 (rubber crush 40°, A thickness of 1 mm) was formed. A fluorosurfactant EFTOP is added into the silicone rubber layer 5. tilH% was added. Furthermore, a conductive brush 20 was brought into contact with the surface layer 5 of the pressure roller 1, as shown in FIG. 2, to remove the electric charges on the surface of the pressure roller 1.

By adding EFTOP to the surface layer 5 of the pressure roller 1, the surface potential of the pressure roller 1, which was conventionally -2 KV or more, was reduced to -several hundreds of square meters.

A durability test was conducted by attaching the fixing device having the configuration shown in section 1'A to a TheBeam printer using negative toner. According to the test results, toner offset was reduced and there was almost no 7Ij error on the cleaning pad 9. In addition, there was almost no change even when 100,000 sheets of transfer paper were passed through 6 sheets (sheet feeding speed: 8 sheets/min). Furthermore, when cleaning pad 9 contains not only silicone oil but also a fluorine-based surfactant in an amount of 9% of 0.5 to 10 tons based on the silicone oil, the toner offset becomes more accurate and good results can be obtained. Ta. Furthermore, the durability of the pressure roller 1 itself has also been improved.

Figure 3 shows book 9. Another example of a river is shown. In this example, a cleaning valve 19 for the constant n roller 2 was not provided, and the constant ri roller 2 was not coated with silicone oil. The surface of the fixing roller 2.

PFAIj with a thickness of 0.1 mm interspersed with carbon powder 1
4 resin layer 7, and the core bar 6 is grounded by a plate spring or the like (not shown).The carbon mixed in the PFA resin layer 7 is preferably 0.1 to 5%. By adding such carbon, it was possible to significantly reduce the surface potential (+2 KV or more) of the fixing roller 2 due to frictional charging.

The pressure roller l has a sponge layer 4 of porous silicone rubber containing a fluorine-based surfactant, and a silicone rubber layer 5 similarly containing a two-way surfactant on the surface thereof. The metal 3 was grounded via a four-core bearing or a conductive spring (not shown).

The sponge layer 4 of the pressure roller 1 contains a fluorine-based surfactant in an amount of 0.01 to 3.07% (preferably 4%, based on the total amount of the rubber). Doing so may cause vulcanization failure or foaming failure, and 0.01%
If it is less than this, the problem arises that it is not possible to impart tetraelectricity. In this example, O.

1 to 0.574% was added.

The fixing device of this example was installed in a laser beam printer using negative toner described in 11), and the same durability test as in Example 1 was conducted. 50,000 sheets (paper feeding speed: 5 sheets, 'min) I! I! I continued printing, but without applying silicone oil and using the conductive brush 2 as shown in Figure 2.
There was no need for contact with zero, there was almost no toner offset, and good results could be achieved with IJ.

In the embodiment L, the sponge layer No. 4 of the pressure roller 1,
The resistance of the sponge layer 4 was lowered by adding an elementary surfactant, but another method is to fill the sponge layer 4 with conductive am such as carbon fiber instead of the 77-g surfactant. You can also use this method.

FIG. 4 shows a pressure roller 1 of a fixing device according to yet another uninvented embodiment. According to this embodiment, a silicone rubber layer 5 to which a base surfactant has been added is pressed. It extends to the end of the roller 1 and is configured to release itt load generated on the surface of the silicone rubber layer 5 via the core metal 3. Therefore, there is no need to make the first elastic layer 4 of the pressure roller conductive, and there is no need to bring the conductive brush into contact with the roller surface. All you have to do is ground the core 3 by contacting it with the gold 3.

gl ['s] L-ri unreleased 1 multi-1 is configured as described below, and therefore produces the effects described below.

In other words, the sponge-type elastic rotating body according to the present invention contains a fluorine-based surfactant at least in the surface layer of the elastic rotating body, thereby reducing the electrical resistance. It has the advantage that it can lower the electric potential and significantly reduce toner offset, and can be suitably used for elastic rotating bodies and fixing devices such as printers.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a fixed radius device according to the invention. FIG. 2 is a cross section [4] of an elastic rotating body according to the present invention. FIG. 3 is a sectional view of a fixing device according to another embodiment of the present invention. FIG. 4 is a longitudinal sectional view of another embodiment of the elastic rotating body according to the invention. FIG. 5 is a sectional view of a conventional fixing device. 1: Pressurizing elastic rotating body 2: Fixing rotating body 3: Core bar 4: First elastic layer (sponge layer) 5: Second elastic layer (silicone rubber layer) 8; Halogen heater 9: Cleaning pad 15: Transfer material 16: Toner 20: Conductive brush

Claims (1)

[Scope of Claims] 1) In an elastic rotating body having at least an elastic layer, a first elastic layer is provided as the elastic layer, and a surface of the first elastic layer has higher hardness and thickness than the first elastic layer. and a thinned second elastic layer, wherein at least the second elastic layer contains a fluorosurfactant. 2) The elastic rotating body according to claim 1, wherein the first elastic layer is made of porous silicone rubber. 3) The elastic rotating body according to claim 1 or 2, wherein the first elastic layer is electrically conductive. 4) Fluorine surfactant is 0.003 to 1.0% by weight,
The elastic rotating body according to any one of claims 1 to 3, preferably containing 0.01 to 0.5% by weight. 5) Fluorine surfactants include perfluoroalkyl polyoxyethylene ethanol, perfluoroalkyl carboxylate, perfluoroalkylammonium salt, perfluoroalkyl betaine, perfluoroalkyl amine oxide, perfluoroalkyl ethylene oxide adduct, perfluoro The elastic rotating body according to any one of claims 1 to 4, which is one or more selected from alkyl phosphate esters and non-dissociable perfluoroalkyl compounds. 6) The elastic rotating body according to any one of claims 1 to 5, wherein the elastic rotating body is roll-shaped or belt-shaped. 7) A fixing rotor having a release layer formed on its surface and heating and fixing the toner image onto the transfer material; and a pressing elastic rotor having at least an elastic layer and pressing the transfer material against the fixing rotor and transporting it. In the fixing device, the elastic layer of the pressurizing elastic rotating body includes a first elastic layer, and a surface of the first elastic layer that has a higher hardness and a thinner thickness than the first elastic layer. a second elastic layer, wherein at least the second elastic layer contains a fluorosurfactant. 8) The fixing device according to claim 7, wherein the first elastic layer of the pressurizing elastic rotor is made of porous silicone rubber. 9) The fixing device according to claim 7 or 8, wherein the first elastic layer of the pressurizing elastic rotor has electrical conductivity. 10) Claim 7, characterized in that the elastic layer of the pressurizing elastic rotating body is formed on a core bar and grounds the core bar.
The fixing device according to any one of Items 1 to 9. 11) The releasable layer of the fixing rotor is made of a copolymer of tetrafluoroethylene resin and perfluoroalkoxyethylene resin (
PFA)
The fixing device according to any one of Item 10. 12) A method for supplying silicone oil or silicone oil and a fluorosurfactant to the fixing rotating body or the pressurizing elastic rotating body.
The fixing device according to any one of Item 11. 13) The fixing device according to any one of claims 7 to 12, wherein the fixing rotating body and the pressing elastic rotating body are roll-shaped or belt-shaped.